Sunday, August 16, 2020



 Three of us headed from Baltimore in search of piemontite on a hillside near Hamiltonban Township in the South Mountain area of Adams County, Pennsylvania. We parked along Mount Hope Road near Gum Springs Road. If we were going to find piemontite  we knew it would occur in outcrops where reddish pink metarhyolite dominated. Soon we were following a trail along the base of the ridge.


Within a few minutes, we spotted some large boulders through the trees. Although no hint of a trail led to them, we bushwhacked about 20 yards uphill,  found the reddish pink metarhyolite we were looking for and soon spotted some piemontite. It occurs mostly in adamantine radiated microscopic prisms exclusively at or near where  quartz has intruded the metarhyolite. We believe we were in one of six known South Mountain area piemontite localities, at least four of which date from the 1890’s

We were also within about a quarter mile of seriously overgrown dumps from copper prospects dating back yet further into the 19th Century.  This was one of  about 20 known localities for native copper in the South Mountain area. Always found in volcanic metabasalts,  the copper was from deposits that were much smaller than but otherwise closely resembled the enormous and lucrative Keeweenaw deposit in upper Michigan. Although extensively prospected well into the 20th Century, the copper never proved plentiful enough to be viable.  

The South Mountain area has long fascinated geologists.  Their focus has always been less on the copper than  the geologic history exposed by rocks over hundreds of millions of years of  erosion.  Research regarding the  piemontite occurrences, while thorough and specific, was limited to separate studies. 

This region prominently straddles the Maryland line into Frederick County, where the geology is similar. The Pennsylvania side calls it South Mountain, Maryland calls it the Catoctins. Geologists have extensively studied the rocks on the Maryland side as well.  Nearly all the studies, however, have been specifically  limited either to Pennsylvania or to Maryland.

Some of the Pennsylvania studies at least acknowledged the presence of piemontite, even though sometimes referred to as “rusty epidote,” or "piedmontite."   In one of a series of articles entitled Chronicles of Central Pennsylvania Mineralogy, the late Jay Lininger described the phenomenon: "Like the comedian Rodney Dangerfield who didn't get no respect." In Maryland, piemontite got less than no respect.It has received no mention. 

Yet, piemontite has aesthetic qualities that make it a highly appealing mineral species as a member of the epidote group, like zoisite and allanite.  John Sinkankas in Gemstones of North America even listed “piemontite in rhyolite” as “semi-precious gem cutting material.” Its presence shows less weathering and better luster within freshly broken rock. Though usually in radiating microscopic crystals as described, a few specimens that are less common bear larger crystals up to about 15 mm. x 3 mm.  Nearly all such crystals have been fractured upon recovery. Seeing perfection is unrealistic. Piemontite is neither common nor highly valued relative to many other species, but regard for it is rising. .

A few years ago, this writer was working a booth at a show in the Towson, Maryland Armory. A man walked by with the most spectacular South Mountain piemontite specimen I’ve ever seen. I’m sure he intended to sell it, but he did not mention a price. After I complimented the specimen, he moved on. Had this happened today, I would happily have emptied my wallet.

Nothing short of synchronicity could make sense of how this writer personally collected piemontite in Maryland’s Frederick County only three weeks before our recent collecting trip. I was clueless that piemontite was in a specimen picked up in a field less than a mile down a road leading west from the tiny hamlet of New London.

 In typical fashion, I had stopped to check out some minor excavation and a small pile of rocks and dirt along the south side of the road.  Standing out among the rocks lying on the ground was the piece of pink metarhyolite pictured above at right.  Just as I knew that  metarhyolite of such color existed in Frederick County, I also realized how conspicuously misplaced it seemed compared to other surrounding rocks. So I picked it up and took it home. No thought of piemontite ever entered my mind. Upon arriving home, I threw it onto the rock pile in my back yard and never mentioned the find to anyone.

Three weeks later by sheer coincidence, a collector called and asked me to join him to look for piemontite in Adams County and write a post about it if we found any.  We went, we found piemontite, and it was obvious that the material in which we found it was the same as the piece I’d collected near new London. Doing my research, I read something in the aforementioned article by Jay Lininger that aroused my curiosity. The article stated that that the renowned late geologist Dr. Florence Bascom, in a her PhD thesis about piemontite,  proved that some of the pink colored rhyolites drew their color from included piemontite.I should mention that Dr. Bascom was the first woman in the United States to earn a PhD in geology and later went on to establish the Geology Department at Bryn Mawr University.

So I went out to the rock pile in the back yard and grabbed the metarhyolite I’d found near New London. A presence of piemontite was readily apparent. I did not report this as a new find for Maryland because it seemed quite obvious that the specimen was not indigenous to the field where I collected it.

However,  metarhyolite has an established presence just a few miles further west of New London  in Maryland’s Catoctins. As long a some of it is the same color as the  ubiquitous reddish metarhyolite on the Pennsylvania side of the state line, piemontite will very likely be present., Once uncovered and verified, it could be a legitimate new find for Maryland.    

Wednesday, May 6, 2020

Remnants of Maryland's Historic Patapsco Mine

Those in regional mineralogical circles know that the internationally cherished bright silvery cobalt bearing sulfide carrollite is eponymous with Carroll County Maryland. Carrollite, best known for magnificent cubo-octahedral crystals from Democractic Republic of Congo, is the only mineral species of the more than 5,000 that are known for which Maryland is the type locality.  A  2009 Mineral Bliss post  explains the interesting mineralogy relating to the  "carrollite" as it occurs  in Carroll County.

The specific type locality for carrollite in Carroll County was known as the Patapsco Mine(s), an operation that actually consisted of two mines: the Orchard Mine and the Wildeson Mine. Mining commenced in 1850 at the Wildeson Mine and in 1851 at the Orchard Mine. Both sites were mined for copper and by the 1870's iron.

A costly attempt to exploit a 1852 discovery  of a vein rich in cobalt ore led the identification and subsequent publication of carrollite.  It also led to the financial failure of the mines in 1854. Thereafter mining  resumed for copper through leases and different ownership.

Soon after the discovery of carrollite, specimens bearing similar cobalt sulfides turned up elsewhere in southeastern Carroll County's Sykesville Mining District at the Mineral Hill Mine and the Springfield Mine. These occurrences were small enough that mining was never considered. 

At least a few of the  dumps, shafts, and pits of the Patapsco Mines, though overgrown and difficult to locate, were still accessible to a few cognoscenti in the late 1990's. By the turn of the millennium, remnants of the mining had been reclaimed or were considered to be lost. Collectors demonstrated minimal concern. The same kind of material  the Patapsco Mines had yielded was easier to collect on the dumps of the Mineral Hill Mine. 

A collector friend succeeded in locating what appeared to have once been a pit from one of the Patapsco Mines.  On the ground nearby, we found lying on the ground several decent magnetite specimens with notable cleavage as well as rocks bearing significant malachite. Also present in a few rocks were very small amounts of epidote, pyrite, chalcopyrite, and bornite. We found no evidence of "carrollite."

After penetrating the surrounding dirt with a garden trowel, we found more that was too dirty to examine on site.  The highlight of the day presented itself inside a rock that we broke open. Pictured at right,  it appears to be chrysocolla,  albeit  of a deeper blue color than expected, some of which visually almost visually suggested azurite.  The Natural History Society of Maryland's 1940 Minerals of Maryland publication by Ostrander and Price reported both species.

Having found significant  magnetite but no hint of cobalt sulfides (carrollite), we  believe that our filled in with soil apparent former pit may have been associated with the Orchard Mine. We base this conclusion on a Summer, 1998 article by Johnnie Johnsson in Matrix: A Journal of the History of Minerals (also our source for specific earlier given dates) that limits discussion of carrollite to the Wildesen Mine.

The same literature from 22 years ago describes other workings of the Patapsco Mines in a manner that  begs for exploration. It mentions  a "600 foot adit for extraction or drainage purposes." as well as  "depressions in the area of the site near the river that could be from prospecting work, an adit, or remnants of the wheelhouse, crusher or furnace structures."                                                                                                                                       
There may yet  be more to seek.


Wednesday, August 21, 2019

Scoring East Coast Mineral Specimens at the East Coast Show

For serious aficionados in the eastern and northeastern United States, the annual East Coast Gem, Mineral, and Fossil show in West Springfield, Massachusetts, each year on the second weekend of August, is a summer highlight.   It happens Friday through Sunday and fills the Better Living Center at West Springfield's Eastern States Exposition. The focus of this post limits itself to finding dealers  at this show with significant quantities of East Coast-collected specimens available for purchase. These specimens, most  collected in the northeastern United States, show up almost exclusively amongst the retail dealers in the Better Living Center as opposed to those in the adjacent building, where the merchandise is devoted to wholesale trade.

This  largest gem, mineral, and fossil show to happen in the Eastern United States is much the same every year. A special and impressive mineral exhibit from a well-known collection always adorns an entrance  area leading  to the wider space where lines of merchandise fill a dozen aisles of tables and shelves manned by about 150 dealers. A few of these dealers sell significant quantities of East Coast-collected mineral specimens. In nearly all cases, the prices are fair, sometimes bargain level.  With few exceptions, dealers return each year to the same spot they occupied the previous year. In that regard, this post could be helpful to collectors of East Coast minerals here in future years.

In 2019, however, some of  the best East Coast  bargains were offered by a first time vendor at an easy to miss table in the farthest corner from the show's entrance point. There, Bob Batic of Mountville, New Jersey traded as Bob's 2nd Act Collectibles. His  personal collection was among those featured in the 2016 Mineralogical Record Supplement  Mineral Collections in the American Northeast.  For years, Bob's collection has evolved from worldwide with an East Coast emphasis to specializing in vintage East Coast specimens collected between 1875 and World War II.  The transition produced plenty of notable specimens to sell, especially from older East Coast finds. Collectors found many of the prices to be irresistible.

Two rows past Mr. Batic, our visit to the busy Adironcack Fine Minerals table was too short.  At least there was time to photograph part of the wide selection of East Coast Minerals to use as the title image for this post. The merchandise was attractive and reasonably priced Adirondack Fine Minerals  also had a massive selection of large Herkimer Diamonds.

Three tables away on the same side of the aisle,  Robert Rosenblatt traded as Rocko Minerals. A fixture at numerous  East Coast events, his true-to-form  selection of minerals was abundant in rare, and/or unusual, and ultimately collectable East Coast specimens at reasonable prices. Three such pieces proved irresistible to the personal mineralogical sensibilities of this writer:  brazilianite crystals measuring to 2 cm. from Newport, New Hampshire;  a gahnite floater to 3 cm. from Mount Apatite, Maine; and a  beautiful thumbnail with a 1.1 cm. zircon crystal on matrix from Blackberry, New Hampshire atop a cluster of smaller  zircon crystals.

Across the aisle between Adirondack Fine Minerals and Rocko, Geologic Desires has long been a major attraction not only at this East Coast Show, but  at other venues extending to larger ones in Denver and ultimately Tucson.  Owner Michael Walter has always made a point of featuring specimens that he and his associates have mined  in St. Lawrence County, New York, which is the convenient location of his home and business. Often working in partnership with property owners, Walter uncovered  and mined prospects that already have a reputation for being classic East Coast localities. Every year, Michael comes to the East Coast Show with new finds.   An important find this year was a combination of calcite, quartz, and hematite  from "the Dafoe Property" in St. Lawrence County. He uncovered these specimens there after several years of marketing and mining  tourmaline crystals with visual similarities to the already classic dravite genre he previously  brought to market from the nearby Powers Farm.

Two aisles beyond, Jason Baskin's Jay's Minerals of Flemington, New Jersey, continues to be a must stop for East Coast material . As always, large quantities of just a few East Coast genres define the pickings. This year, one such genre was an extensive array of orange stilbite crystals from Moore's Station in Mercer County, New Jersey. Jay's  Minerals is best known for its seemingly endless supply of now classic almandine garnets in graphite from the Red Embers Mine in Ervine,Massachussetts, where Baskin has an exclusive lease. The mine's name refers to the exquisite red hue these garnets display when light is placed beneath them.  They may well have been the most popular single item in the show every year since first appearing here in 2014. Thereafter, especially since launching here in 2015  his serious find of amethyst crystals from Moosup, Connecticut, Jay's Minerals, like Geologic Desires, has attracted buyers eager to be in on what is new. This year he offered recently uncovered  chrysocolla specimens  from Bound Brook, New Jersey in an assortment that included some polished slabs

Two aisles past Jay's Minerals, Mark Gottlieb, of North Granby, Connecticut had some interesting East Coast specimens,  many that he personally collected, at very reasonable prices. Included were some very intriguing  cabinet sized clusters of milky quartz crystals from Moosup Connecticut. For this writer, a Marylander with ties to collectors and clubs that enjoy collecting  at the National Limesone Quarry in Mt. Pleasant Mills, Pennsylvania, the huge selection of strontianite from that locality was notable

Across the isle,  the Yankee Mineral and Gem company of East Hampton, Connecticut offered an interesting selection of East Coast minerals.  Particularly intriguing this year  was a stock of wolframite pseudomorph  after scheelite specimens from Old Mine Park in Trumball, Connecticut. Most  were in the $50 range. However, one particularly nice example of the genre was priced at $650. And having previously been skunked after hiking up a mountain to collect at the Lord Hill Mine in Oxford County, Maine, seeing a sizable box of Lord Hill blue beryl crystals, most selling for about $5, once again struck a personal chord.

Collection Arkane, a prominent Canadian dealership from Mt. St. Hilaire, Quebec, had many fine  minerals from localities in eastern Canada that were  no further away from West Springield than many localities in the northeastern United States.The wares included attractive, diverse, and fairly priced suites  from Mt. St. Hilaire, Francon Quarry, and the Jeffrey Quarry in Quebec. From more distant spots, but worth mentioning, was a large group of  specimens from the ever popular Rapid Creek locality in the Yukon Territory.

In the next aisle,  Nature's Choice from Newington, Connectictut, despite a worldwide focus, had plenty of  East Coast specimens, enough to be worthy of  a stop for collectors seeking them. Most were priced  in the $10 to $25 range and from Massachusetts or Connecticut.

As our one day at the show, which was intended only for buying, neared an end , the decision was made to put  together a post about its availability of East Coast minerals. This entailed once again seeking out all the dealers we had observed with conspicuous quantities of them available. Very likely, a few of the finest specimens in the show could have been offered by some of the show's prominent  high end dealers who are widely known far beyond the Eastern United States. Our assumption is that the  relatively few collectors in attendance who were looking to buy such specimens would know where to find them. We extend our apologies to any dealers with significant quantities of East Coast specimens whom we failed to cover.

Saturday, August 3, 2019

The Garnets of Stony Run in Baltimore City

A new garnet locality has emerged in Wyman Park along Stony Run. It has produced crystals that visually resemble those pictured above. They were collected about a third of a mile upstream at the historic long closed and built over Wright Quarry.  The new spot  is along a short stretch of Stony Run between the Wyman Park Drive Bridge and where it enters a tunnel before flowing into  Jones Falls en route to Baltimore Harbor.  

Mineral Bliss  was here before in conjunction with a 2014 post.  Its subject was a piece of quartz we found in the stream that hosted several white concentric circles, which rendered us "stumped." We now suspect these circles were once a contact point for small stalactites or stalagmites that had  long ago originated within a cavity in rock somewhere upstream.

On a recent steamy July Sunday,  local aficionado and collector of regional minerals Stuart Herring directed our second visit. We came to look for garnets, and we succeeded in finding them.  

Jones Falls Schist and hornblende rich Baltimore Gneiss share the country rock everywhere that Stony Run flows through Wyman Park. Intruding the schist and gneiss are at least three separate pegmatite dikes. They differ according to  varying proportions, hues, and varieties of quartz, mica, and feldspar minerals. Interestingly and importantly, all three pegmatites have yielded similar gemmy red almandine garnet crystals. 
Heading downhill  through overgrown brush to reach the stream  from the west side of Remington Avenue below Wyman Park Drive was easier than it was 5 years ago. Since then, a diagonal swath extending about halfway to the stream was created to allow heavy equipment to descend, then dig and blast as  necessary to replace a decaying sewer line. The blasting dislodged a significant amount of pegmatite rock from beneath the soil. Some of the pieces made their way further downhill toward and into the stream. 

Directly across the stream from where we approached is a much steeper embankment that exposes a contact point between the Jones Falls schist and a pegmatite dike. The recent blasting suggests that very likely this same pegmatite once extended to our side of the stream. Comprising it are differing amounts of microcline, albite, and plagioclase feldspar along with quartz and mica. 

The garnet crystals within rarely measure more than 1/2 inch. Mostly they reveal themselves inside the pegmatite rock when it is broken, which unfortunately is likely to damage many of the crystals. We obtained our garnets, such as pictured at right, by hammering away at a few  rocks and cobbles plucked from along the stream bank and in the stream. 

After a little more than an hour, we headed upstream to the area where Stony Run flows past the former Wright Quarry site.  Our approach was longer than the previously mentioned 1/3 mile and roundabout to avoid impenetrable  vegetation. Along the way, Stuart pointed through a wooded  area where several years ago, the City had blasted into a different pegmatite  where a tannish microcline was dominant. Once again, the City's  purpose had been to replace a portion of aging sewer line,  The blasting produced and revealed numerous garnet bearing pegmatite boulders. They remained at the site long enough for Stuart to accumulate an attractive selection of specimens  bearing attractive almandine crystals resembling those we'd just collected. Ultimately the material was  hauled away with no trace remaining. 

The former Wright Quarry site was more approachable. A pegmatite consisting primarily of white albite once intruded through its walls.   In earlier times, reports show this pegmatite yielded not only garnets, but beryl, zoisite (var.) thulite, fluorapatite, and autunite.  Long after the Wright Quarry closed and even as the Johns Hopkins University campus extended into and over its site,  a few garnet yielding  pegmatitic rocks from the old Wright Quarry dumps remained above and along the stream banks. 

They disappeared in recent years during a Baltimore City Department of Public  Works project that reinforced the stream bank to slow erosion. When the work was complete, the few rocks and boulders once part of the Wright Quarry dump were nowhere to be seen. Sometime thereafter Stuart noticed a few pieces of material that looked like Wright Quarry albite in the stream near its now reinforced bank. He suspected that some of the Wright Quarry rocks and boulders  could have  ended up beneath the recently reinforced stream bank from which storm currents could have dislodged them. 

We pulled two such rocks out of the stream, each weighing several pounds  When cracked open, portions of both rocks revealed hundreds of  tiny, mostly broken gemmy red garnet crystals measuring from one to two millimeters. Such ubiquitous small garnet crystals have long been considered definitive of Wright Quarry pegmatite and never known to be present in other  nearby pegmatites. Pictured at right is is a large fragment from one of the rocks we collected. It is  reasonable to believe that it could be one of the last examples of Wright Quarry garnet to be found. 

Tuesday, July 16, 2019

Pink Quartz, not Rose Quartz in Harford County, Maryland

The question is whether the above pictured image is actually rose quartz. This writer collected it in Southeastern Harford County, Maryland. Rose quartz has never  been officially identified and verified as occurring in Maryland. 

Numerous well-versed regional authorities who viewed this specimen have given different reasons why they believe it is not rose quartz. While most of them were credible, none were scientific. “You could call it rose quartz" was as close as any response came to a confirmation of rose quartz. However, it went on to note: "It's just not quite the right color.” 

The genuine rose quartz specimen  at left was placed amidst a varied  assortment of quartz cobbles and pebbles that members of a family collected in the woods behind their house. On a recent visit, the specimen in our title picture turned up after we had spent about 15 minutes turning over rocks in their woods. It visually resembled the uncontested rose quartz specimen as much as any of the previously collected pieces shown at right. 

The locality is a wooded area to the southwest of Rt. 152 about 2 1/2 miles northwest of I-95. It is at a point where Maryland's Coastal Plain intersects with its Piedmont. Small cobbles of quartz and quartzite  along with a few less distinctive metamorphic rocks are ubiquitous underfoot. Nearly all of the quartz and quartzite show color: red, yellow orange, brown, and ---yes pink. These colors result from a presence of iron oxide, typically hematite, that has stained the quartz and has often become included within as the quartz formed millions of years ago from a complex sequence of geological events. 

By the standard definition, rose quartz owes its color to inclusions of crystals of one, possibly other minerals within the quartz. Staining is never a factor. The inclusions are separate, miniscule and all but impossible to separate so that  analysis of them by x-ray diffraction is rarely possible.

Mindat cites two studies stating that massive rose quartz always has a "hazy to translucent character due to microscopic fibrous inclusions of a pink borosilicate mineral related to dumortierite." The likelihood is all but nil that inclusions of such a species, which is not known to occur in Maryland, would show up within quartz pebbles exclusively in an area where most of the quartz shows iron oxide staining and/or inclusions. Without analysis or a nearby presence of verified rose quartz, a better option is to call the material “pink quartz.” 

It takes a good polish, has more variants, and can be just as pretty.

Thursday, July 19, 2018


Pictured above is a specimen of serpentine collected circa 1940 at the chromite bearing serpentine barrens of Bare Hills in Baltimore County, Maryland. It is one of several such specimens The Natural History Society of Maryland owns. Very likely Charles Ostrander and/or Walter Price, the Society's  prominent curators at the time, collected them. The NHSM labels identified the specimens as  "baltimorite". Minerals of Maryland, the NSHM publication that these two curators co-authored in 1940, may have been the last regional publication to suggest that "baltimorite" was  a species or variety of a species.

 Mindat describes  baltimorite as a "synonym for antigorite." along with 11 other names including "gymnite" and "porcellophite." Interestingly, Minerals of Maryland refers to "gymnite" and "porcellophite" as separate minerals that also occur,  along with "baltimorite," at Bare Hills.  The three names  have since all but disappeared from mineralogical parlance, although  Bernard and Hyrsl's Minerals and Their Localities refers to gymnite as a synonym for deweylite,  which is typically identified as a mixture of several varying different species that can occur  together at some of central Maryland's serpentine outcrops.

In addition to naming twelve antigorite synonyms, Mindat also names eight varieties of antigorite. Two of them, williamsite and chrome antigorite,  are known to those who collect in the serpentinized areas of Central Maryland and Southern Pennsylvania. Highly valued  in lapidary circles, williamsite is  best described as a  solid and translucent apple-green antigorite included with specks of black chromite. Chrome antigorite displays varying amounts of reddish purple coloring attributed to the presence of chromium. It is usually columnar or fibrous and known to occur primarily at the now off-limits Woods Chrome Pits in Lancaster County, Pennsylvania  just a few miles north of the Mayland state line.   

Antigorite, lizardite, and chrystotile are the best known of 13 species in the serpentine subgroup. In addition to these 13 species, the serpentine subgroup as an entity boasts eight varieties, none of them approved as species in their own right.

 One such serpentine subgroup varietiy is picrolite. Mindat defines picrolite primarily by habit  as "a columnar or coarsely fibrous (non - asbestiform) variety of serpentine commonly referred to as a variety of antigorite, but may be other species." The most common of these "other"  species are the serpentine subgroup mineral species lizardite and chrystotile. Picrolite is ubiquitous at nearly all the serpentine exposures in central Maryland and southern Pennsylvania. Note the label on the NHSM specimen at right : "Serpentine, var. baltimorite (Picrolite). It makes sense. Here it can be assumed that the term picrolite was used to to refer to the columnar habit of the sample.  The original material that was given the name baltimorite in 1843  and  wherever else the name was used thereafter matched the Mindat description of picrolite. Typically the color of picrolite is green as shown in the image at left. Interestingly the color of  the several "baltimorite" specimens at NHSM---which are the only specimens anywhere so labeled that we are aware of--- is  brown.  Would it be unreasonable to colloquially refer to picrolite of brown color as "baltimorite?" An interesting aside is that the approved species known as "chrome antigorite," like picrolite, is almost always columnar.

It was Thomas Thomson, a British mineralogist, who came up with the name baltimorite in 1843 (Phil.Mag.22, 1911). He had recently received a specimen from the well-known American scholar and collector Francis Alger. Collected at Bare Hills in Baltimore County, the specimen was opaque with a silky luster and consisted of longitudinal fibers that adhered to each other. Alger had referred to the material as "asbestos and chrome."Thomson studied the specimen. After ruling out the presence of asbestos as well as chromium, he named it baltimorite for the locality.

Two  years later, citing Peggendorff's Annals, Vol. lxii, p. 137, The Edinburgh New Philospophical Journal, Volume 39 published in an article that the German mineralogist Karl Friedrich August Rammelsberg had found that Thomson's "baltimorite" was identical  to other material that had  become known as chrysotile by Kobel.  Franz Kobel  was another German mineralogist, who had originally called the material Schiller asbestos. The conclusion: "As the latter (baltimorite) was described subsequently to the former, the name of baltimorite must be given up."

However, the baltimorite handle endured, only to receive an additional blow in 1855 by a supplement to Dana's The System of Mineralogy. Therein it was noted that two years earlier,  the German mineralogist C. von Hauer had published a new analysis of purported baltimorite in which the chemical composition varied from the original composition given by Thomson. The Dana supplement concluded: 
We have a new analysis of a stone which somebody has labeled baltimorite. It is very wide from the original baltimorite of Thomson (from Bare Hills, Maryland) and is no better entitled to the name than many other fibrous stones that could be gathered from our serpentine regions.
 Eighty one years later in 1936, the American Mineralogical Association placed the final nail in "baltimorite's" coffin. The American Mineralogist in an abstract of a paper by George C. Selfridge, Jr.  of Columbia University entitled "An X-ray and Optical Investigation of the Serpentine Minerals" proclaimed on page 463:
Based on the results of the x-ray and optical studies and the chemical discussion---to drop the names picrosmine, picrolite, williamsite, bowenite, porcellophite, and baltimorite  for the term antigorite. The term serpentinite is suggested for rocks composed of serpentine or antigorite or a mixture of both. 
The recommendation came at about the same time as the mineral aficionados at NHSM were collecting and labeling "baltimorite" specimens from either Bare Hills or the geologically similar Soldiers Delight serpentine outcrops, also in Baltimore County. Interestingly, the NHSM labeled as "picrolite" numerous specimens from serpentine outcrops in Maryland's  Harford County that appeared to differ from those labeled "baltimorite" only by their green color.

Then in 1956, in Vol. 41 of  The American Mineralogist,  a 21 page paper by George T. Faust and Bartholomew Nagy outlined studies showing "that minerals classified as serpentines are either chrysotile,  antigorite, or natural mixtures of these two minerals--- It is suggested that serpentines should be redefined in terms of the relative proportions of antigorite and chrysotile"

Notwithstanding, the endless questions, answers, and names involving  various species and varieties in the Serpentine Subgroup have continued---and undoubtedly will continue--- to evolve without reference to baltimorite  For now, here is the best definition for baltimorite we've been able to come up with:  an obsolete and antiquated synonym for picrolite, a serpentine group variety, which depending upon composition may actually be antigorite, lizardite, chrystotile, or a combination of them.

We are grateful to John S. White, Past Curator in Charge of the Mineral and Gem collection at the Smithsonian's National Museum of Natural History for suggesting this story, turning us on to some of the referenced sources, and proofreading it. 

Wednesday, March 7, 2018

Leesite: Another New Species Discovered by Patrick Haynes


Patrick Haynes
In  1989, Patrick Haynes collected what 27 years later would become the new uranyl oxide micromineral leesite. Its locality is the Jomac Mine in White Canyon, San Juan County, Utah.  It is the locality, where at about the same time, Haynes  discovered two similarly rare and microscopic uranium bearing species, blatonite and oswaldpeetersite.   The name leesite is eponymous with Brian Lees, the legendary owner of Collector’s Edge.

Soon after collecting it, Haynes examined material under the microscope and assumed that it should be an identifiable species. The orange color led him to suspect it to be fourmarierite or curite. He submitted it to Dr. Michel Deliens at the Royal Belgian Department of Natural History in Brussels, Belgium along with other material, which the International Mineralogical Association (IMA) would later approve as blatonite and oswaldpeetersite.  The verdict on the future leesite suggested that it was a combination of species.

Ten to fifteen years later, Haynes learned about success at identifying difficult new species by  Dr. Frank Hawthorne, Professor of Mineralogy and Crystallography at the University of Manitoba.  He sent a sample of the orange unknown material to Dr. Hawthorne to examine. Like the scientists in Brussels, Dr. Hawthorne believed it could be a mixture, but this time of a different combination of minerals.   

Haynes  explained:

Leesite is very fine-grained, and it is commonly associated with another orange potassium uranium oxide called compreignacite, which can make sample preparation very difficult. With the few "coarser" crystals one can generally make a visual determination, but that is unusual.

A few years later Pat became aware that Travis Olds and Tony Kampf had been “working up these ridiculously tiny minerals from Utah.”   Around that time, Haynes encountered Dr. Peter Burns from University of Notre Dame, under whom Olds had studied when earning his PhD. He sent samples of the questionable material to Dr. Burns and PhD students to study. Dr. Olds, now a post-doctorate researcher at the University of Washington and his associates produced a successful and convincing analysis. Then Tony Kampf and several other mineralogists provided further input. The result was the submission of an abstract to the IMA for approval  of a new species, to be named leesite. The approval came in 2016.

IMA rules stipulate that approval of a new species becomes official only after the authors of the abstract seeking that approval have published a synopsis. That happened in January, 2018, when the American Mineralogist published a synopsis of leesite by Olds, Kampf, et al. Patrick Haynes believes that only 130 samples of leesite are known to exist.  All of them, were collected at the Jomac Mine, which was reclaimed in 1992, and leesite has been reported from no other locality on earth.