Thursday, October 13, 2016

Baltimore County's Historic Milford Trap Quarry

In northwestern Baltimore County, the  Milford Trap Quarry's historic legacy has continued to evolve for the better part of a century since the last of its mineralogical bouny was taken. Those familiar with the site along Milford Mill Road near the Baltimore City line will recall the fire that destroyed a mosque built there  two years after the site sold at auction in 2013. At times between 1950 and then, the old quarry was the focal point of a swimming club along with a teen center and bandstand. The Buddy Deane Show happened there at least once, and scenes from from John Waters' Crybaby and Barry Levinson's Liberty Heights were filmed there.  

Less remembered is the wide range of collectible minerals that the Milford Trap Quarry produced. The Natural History Society of Maryland's long out of print yet still penultimate  guide to Maryland minerals, Minerals of Maryland mentions  "minerals to be found" there in the present tense, suggesting that collecting was still taking place upon its publicaton in 1940. With the exception of Hunting Hill in Montgomery County, which had yet to be "discovered," few if any Maryland localities produced as many different species. Rarely do specimens from the Milford Trap Quarry grace collections or displays. 

The good news is that the Natural History Society of Maryland  has saved and thus preserved what surely must be the premier assortment of Milford specimens as described in Minerals of Maryland. Many appear to be original reference specimens upon which the publication depended.  Early in 2016, the Natural History Society allowed access to many of these long stored away specimens. Among them were many that were particularly notable. 


As ubiquitous as chlorite is at numerous Maryland localities, this one stands out in itsw habit.


This pyrrhotite specimen is notably rich compared to other specimens that have been uncovered in Maryland.  Most Maryland pyrrhotite occurs in a matrix of limestone. Here, it is seen gracing gabbro.


After it had been stored away for many decades, we uncovered this  specimen of the zeolite group mineral laumontite. It is paricularly important for having been the specimen photographed for the inside cover of Minerals of Maryland. 


At the time Minerals of Maryland was published, the Milford Quarry was the only locality in Maryland to have reported scoleite, another zeolite mineral, The species was later uncovered at Hunting Hill in Montgomery County, which is now off limits. The crystals from Hunting Hill, however, were smaller and less showy. We have every reason to believe that this is the finest scolecite specimen ever uncovered in Maryland.


Prehnite is no a zeolite mineral, but typically associated with zeolites and erroneously thought by many to be one. The Milford Quarry was prehnite's only known Maryland locality for nearly a half century. 


Though a common species found at numerous localities, the occurrence of this particularly rich specimen at the Milford Quarry is notable.


Minerals of Maryland notes sphene at the Milford Quarry in "green and brown crystals." Pictured above is a specimen of sphene in green and brown crystals in a matrix of feldspar and metagabbro. 


Clinozoisite as shown above was known to have been abundant at the Milford Quarry and thought to be zoisite. The visual distinction when in this habit is difficcult to make.   

Minerals of Maryland mentions other species known to have been collected  the Milford Trap Quarry  as follows:

Platy ilmenite; pyrite in masses and in crystals; stilbite, natrolite; calcite crystals and cleavages; flattened garnets; black tourmaline crystals; albite; quartz crystals up to five inches long; marcasite crystals and stalactic forms in cavitites; magnetite massive and in brilliant octahedral crystals 1/4 inch across; rutile crystals; horneblende crystals in quartz three inches long; chalcopyrite; radiated actinolite; pyroxene; prochlorite (chromian clinochlore); analcime crystals; laumontite pseudomorph after analcime; epidote in long bladed single crystals and crystalline masses; mizzonite (scapolite); molybdenite; andesine crystals; radiated phillipsite; talc pseudomorph after actinolite; and muscovite.

Friday, September 30, 2016

A New Updated Maryland Minerals Website

For the past month, much of our time has been devoted to working on the Maryland Minerals website, from which the all-important slide show went missing sometime in early September. 

The reason was that Google closed down its Picasa program, which the site had depended upon for our slide show of Maryland -collected minerals. We have since updated the site, replacing the previous Picasa slide show with a more user friendly slide show program that we know our viewers will prefer. 

No longer is the Maryland Minerals slideshow a separate journey through nearly 200 mineral specimens with their labels. That vast series of images now consists of links to separate smaller slide shows, each featuring minerals from different Maryland counties shown in alphabetical order.  The localities within each county also appear in alphabetical order, as well as the specimens that are pictured for each locality. The new slide show will enable viewers to access the images they seek more quickly and efficiently. 

In addition to the list of articles pertinent to Maryland minerals, we have inserted a separate menu that provides a link to the site of this our Mineral Bliss blog.  Other additions include a menu item listing shows in the general region where minerals are displayed and sold as well as a new template for users of the site to contact us. The next change will be to the header image shown at the top of this post, soon to be replaced with one where the rock hammer is surrounded with Maryland minerals. 

We hope you like the new site

Monday, August 8, 2016

New Finds: Falls Road Corridor near Baltimore City Line

Stuart Herring

There is not a field collector anywhere who has introduced this writer to more localities in our native Maryland than Stuart Herring of  Baltimore. For the past two years, his passion has been seeking out unexpected or long forgotten localities by studying old maps. He particularly enjoys exploring unheralded spots  along the Falls Road corridor near the Baltimore City Line just a few minutes from his home. 

On a recent hot August Thursday morning, we visited a talc deposit at the southeastern fringe of the Bare Hills Serpentine Barrens near the contact point between  serpentinite country rock and quartz, schist, or pegmatite, depending upon immediate  direction,  The locality also offers small quantities of  attractive micaceous green chlorite as pictured at right and a few traces of magnetite (rather than the expected chromite). More abundant than the chlorite or magnetite is what appears to be anthophyllite.

Demonstrating a particularly interesting manifestation of the apparent anthophyllite presence is the specimen pictured at left. It bears a stunning visual resemblance to a genre known as Hermanov spheres, eponymous with the locality at Heřmanov, Velké Meziříčí, Vysočina Region, Moravia, Czech Republic.These spheres consist of a phlogopite core surrounded by anthophyllite crystals. In our specimen, the core is actually talc. The crystals surrounding it are talc pseudomorph after anthophyllite. This is the first and only anthophyllite occurrence of which we are aware at the Bare Hills Serpentine Barrens and the chrome pits dotting it. Interestingly, anthophyllite was once quite common in a different geological environment less than two miles away. The locality was the historic Bare Hills Copper Mine located just past the opposite end of the serpentine barrens. At this point, the  serpentinite  has given way to gabbro with hornblende schist and  amphibolite. For the last 55 years, the Bonnie Ridge Apartments has stood where its dumps were previously accessible. 

From the talc locality, we drove to a spot in the Mount Washington neighborhood at a point on Western Run  (not to be confused with Western Run in northern Baltimore County). The location is about 100 yards above where it flows into Jones Falls beneath the Kelly Avenue Bridge. Days before, the area had had endured a flash flood severe enough to extirpate and dislodge many hundreds of previously unrevealed rocks and cobbles.  After parking on Forge Avenue, we walked to the stream. Its banks were strewn mostly with water-polished cobbles of the same gabbro and amphibolite 
that once hosted the Bare Hills Copper Mine.  Another hundred yards above us, a little creek leading  from the site of the former copper mine dumps empties into Western Run. Thus, we kept our eyes peeled for sulfides and malachite patinas, but observed no traces. Of more interest was the occasional epidote group material gracing some of the cobbles. It showed a visual resemblance to  zoisite or clinozoisite. Analysis would be necessary to make the determination. It could also be epidote, which was known to have occurred in similar material less than a mile away at the copper mine.

Another  interesting spot to explore newly uncovered rocks could be farther south along the Falls Road Corridor, especially near Woodberry where Jones Falls flows through the well mineralized Baltimore Gneiss. The same could be said for the Patapsco and the Patuxent Rivers, especially near pegmatite areas.

Monday, July 4, 2016

Chris Luzier and Another Great Maryland Collection

More fascinating Maryland minerals turned up on a recent visit to the home of  Chris Luzier. Chris is the Immediate Past President of the Gem, Lapidary and Mineral Society of Montgomery County, Maryland (GLMSMC). He is also curator of the historically significant suite of Maryland minerals that were once part of the long neglected collection of the  Philadelphia Academy of Natural Sciences.  GMLSMC  obtained this suite from its former member Fred Parker before he moved from Maryland to New Mexico. Parker  had acquired the suite about eight years ago from Collectors Edge, one of  two high-end dealerships that had purchased the collection directly from the Academy for distribution. 

Mineral Bliss had cited these historic specimens in two previous posts after seeing them at the annual GLMSMC Show in Gaitherburg. The original purpose for our visit with Chris Luzier had been to cover them more thoroughly. As we looked over the GMLSMC specimens, Chris made comparisons to interesting pieces in the Maryland suite of his own collection. Two years ago, he displayed some of the better specimens from it at the annual March GLMSMC Show at Gaithersburg  in conjunction with the historic Academy Collection case. 

Maryland's diverse mineralogy has received relatively little attention and recognition in the many decades since Academy Suite was assembled. By displaying as well some of the better specimens in his personal collection, Chris was able to update the historical perspective of the former as well as demonstrate to mineral aficionados that Maryland still has minerals worthy of collecting. 

Many of these specimens were once part of Fred Parker's personal collection along with the historic Philadelphia Academy suite. They include pieces from long closed or lost localities. Some were collected by Parker himself.

In the above picture Chris holds remarkable specimens in each hand  In his right hand is massive magnetite from the historic Mineral Hill Mine in Carroll County.  Magnetite continues to be ubiquitous on remaining Mineral Hill dumps, some that date to pre-Revolutionary times, Massive magnetite boasting such sheen, however, has rarely been encountered at any Maryland locality in recent years. 

Chris has in his left hand a  solid chunk of massive chalcopyrite from New London in Frederick County.  It makes sense that chalcopyrite of such richness could have graced  ore veins extending through the phyllite-laced Wakefield Marble. These veins are known as the New London  (copper) Deposit and were worked  at the historic New London Copper Mine. In the 1960's, similar veins were uncovered at the nearby Farmers Cooperative Limestone Quarry, which closed in 1973. Could Chris be holding the largest Maryland chalcopyrite specimen  known to exist?. 

The brucite specimen at right from Hunting Hill in Rockville, Montgomery County, is similarly
notable.  Fred Parker collected it in September, 2003. Most of what little brucite that Hunting Hill and other less heralded Maryland localities produced is white in color, less crystalline, and mostly opaque. 

The brochantite specimen at left would be unremarkable were it not from Maryland.  As a Maryland example, however, it is noteworthy. Brochantite occurs at several Maryland localities through the Sykesville Formation as well as sparsely associated with other copper minerals in the Wakefield Marble. It is typically difficult to visually differentiate from malachite. Found at the Lehigh Cement Quarry in Union Bridge, this piece was once in the collection of Grant C. Edwards. Is there another example of Maryland brochantite around that's so distinct?

Ugly or not, todorokite was once plentiful at the Medford Quarry in Carroll County, Maryland. In earlier times, collectors assumed the material to be  a curious substance that soiled whatever it touched. They were unaware that it was the complex oxide species todorokite. Sometime later, Fred Parker noted on Mindat that Medford  had yielded  todorokite that was "world class" He personally collected the specimen pictured at right, 

In addition to his Maryland specimens, Chris  maintains an impressive Pennsylvania suite. His specialty is the fluorescent material for which Franklin and Ogdensburg, New Jersey are famous. Occasionally he sells duplicates on the Internet under the handle of  "Abraham Zincoln," in reference to the abundance of zinc bearing minerals from these localities. 

More than any other aspect of his hobby, Chris emphasizes his advocacy of mineral societies and organizations that provide collecting opportunities to members, especially those that seek to engage the interest of young people. He notes that the field trip privileges  that many working quarries so graciously provide to GLMSMC and other groups afford valuable public relations to the companies that own them.  In these times when so many of  Maryland's greatest localities no longer exist, Chris believes that such field trips provide the best opportuntity for  members of such groups to uncover collectable specimens that promote the ongoing study of Maryland's mineralogy.

Monday, May 23, 2016

Maryland Topaz and Maryland Chrome Tourmaline

Additional new images of Maryland-collected minerals are now gracing the slide show on our Maryland Minerals website. More are on the way. They are from the collection of the Natural History Society of  Maryland. It is surely one of the largest and most diverse collections of Maryland-collected minerals in existence. The most glamorous of the specimens are displayed  at the Society's Headquarters at 6908 Belair Road in Baltimore. The Society has stored and preserved hundreds more. Many are the bounty of field trips dating back over 70 years.

If less spectacular to look at than the minerals on display, many of those additional hundreds are highly significant from a scientific and/or historic vantgage point. Included are dozens  of the only known examples of their species to document occurrences named at scores of localities mentioned in the Society's 1940 publication Minerals of Maryland. Often the labels credit one the co-authors, Charles Ostrander or Willaim Price,  with the finds. Two particularly interesting pieces are gem minerals.

The only reference to topaz in Minerals of Maryland is from Alto Dale Farm, which covered several acres at the southeast corner of Reisterstown Road and Cradock Lane in Baltimore County. Houses have completely covered the site for decades. The description noted "white cleavage masses" with quartz crystals" in "soil weathered from a pegmatite dike." The one pictured is the more impressive of two owned by the NHSM. They could well be the only known Maryland-collected topaz specimens in existence.

Another remarkable gem mineral is the chrome tourmaline at right. It is from the Etchison Chrome Mine in Montgomery County. Minerals of Maryland credits this find to the late mineralogist Earl Shannon (1895-1961). It describes the mine circa 1940  as "not been worked for many years, and little of interest remains at the site." The owner was Baltimore's legendary chromium mogul  Isaac Tyson, who also owned the operations at Soldiers Delight, Bare Hills and others extending northeast into Lancaster County, Pennsylvania. Heyl and Pearre later reported chrome tourmaline from the Line Pits, Rock Spring, Maryland. That find, however, lacked the color and luster of the Etchison specimen, Moreover, it is possible that the Rock Spring chrome tourmaline originated in underground workings on the Pennsylvania side of the State Line. Much that was mined there ended up on Maryland bases pits.

Topaz and chrome tourmaline are but two specimens out of nearly 50 NHSM pieces begging to be photographed as well as subject matter for stories.

Tuesday, April 19, 2016

The Carroll Mine in Carroll County, Maryland

The Carroll Mine was one  the four largest 19th Century copper and iron mining operations to exploit Carroll County, Maryland’s Sykesville Mining District. Worked intermittently between the 1840's and 1880, it appears to have received the least attention over the years from the mineralogy community. The copper and iron  bearing species from all four major mines in the District  were much the same. Cobalt-bearing  Linnaeite Group species occurred at all four mines, though not in sufficient quantity for successful commercial production. 
We are grateful to Stuart Herring, a prominent Baltimore-based collector and dealer, whose research led us to the several pits and grown over dumps from these Carroll Mine workings. While trails lead to the only other two mining areas that still exist in the Sykesville Mining District, a substantial bushwhack is necessary to reach the mostly grown over remains from the Carroll Mine.

The Carroll Mine hosted two separate operations at different time periods. Though primarily a producer of iron, at least one shaft was worked for copper by the New Burra Company. The material on the surface around the pits and near the dumps varies. Specular hematite and magnetite are quite easy to find.  Near one of the shafts, most likely the Burra Shaft, are sizable chunks of crystallized epidote, stressed massive garnet, and magnetite. All three host an abundance of copper bearing minerals.


Magnetite---ore quality:

Bornite---ore quality.

Chysocolla is abundant amidst the copper bearing minerals and ranges in color from a pale blue-green to a vivid medium blue.

Lesser quantities of malachite sometimes accompany the chrysocolla, often in small green crystal sheaths.

Chalcanthite and melanterite appear to the naked eye as earthy pale blue crusts hinting at  microscopic crystals, The crystallization becomes clearly evident under the scope. The two species can often be difficult to visually distinguish from each other.

Pyrite and chalcopyrite were present, but not as prevalent as at the Springfield and Mineral Hill Mines. We did not find any cobalt bearing linnaieite-siegenite-carrollite material .

Although native gold has not been reported from the Carroll Mine dumps, we kept our eyes peeled for it. Throughout the area was a fair amount of  white quartz that was weathered in a distinctive manner.  It visually  resembled quartz that once yielded a few  gold particles at an isolated nearby pit, long since built over. .

Wednesday, March 23, 2016

Greenbelt, Maryland’s Phosphate Concretions: 75 Years of Questions

We are grateful to John White and Marie Huizing for procuring  two photocopied articles from 1965 editions of  Rocks and Minerals. The first article is entitled “Unusual Mineral Locality at Greenbelt, Maryland” by French Morgan; the second is a follow-up article  by Dr. Ernest E. Fairbanks, entitled “Remarks on an unusual mineral locality at Greenbelt, Maryland .” The information in these articles proved essential for this post.

Maryland’s only significant phosphate mineral find resulted when in 1941, a knoll  was leveled in order to erect a WWV Broadcasting Station near Greenbelt, in Prince George’s County. Today, the Visitor Center for the NASA Goddard Space Flight Center stands directly on the site.  The above pictured image shows one of many unearthed phosphate-bearing concretion nodules that were collected there in the 1940’s.

It is notable that iron bearing sandstone concretions of similar external visual appearance are common in Prince George’s County northeast of Washington, DC.  However, the only phosphate mineral bearing concretions ever known to occur in the region are from this one specific locality.

Out of curiosity, the late Dr. E. E. Fairbanks of the U.S. Bureau of Mines procured a few of the concretions for examination. The verdict, presumably based on visual observation, was that the phosphate material was dufrenite.  Dr. Fairbanks then provided a number of concretions to Ward's Natural Science Establishment, which subsequently sold them to various dealers and collectors labeled as dufrenite . Some concretions also found their way to both the Smithsonian Museum of Natural History in Washington, as well as the American Museum of Natural History in New York.

During World War II, the U.S. Government closed the area around the towers to the public for safety reasons. However, by 1944, French Morgan and several other members of the Mineralogical Society of the District of Columbia obtained special permission to collect there.  The group collected several dozen concretions that apparently had rolled down a small hill from where grading for the radio towers had taken place. Some of these concretions proved to be more interesting than those found several years earlier.

 In his 1965 article in Rocks and Minerals Morgan mentioned finding limonite, goethite, opal (var.) hyalite, and beraunite  during these later 1944 visits as well as “red, yellow and white minerals as yet unidentified.”  He also   noted “shrinkage cracks lined with microscopic crystals of an unknown mineral.” Specimens of the crystals were submitted to the U.S. U. S. Geological Survey, where according to article they “created no excitement.”

Not until late 1949 or early 1950 did the U.S. Geological Survey become interested in the Greenbelt material. This was after and was probably prompted by a 1949 article in American Mineralogist  by the late Dr. Clifford Frondel entitled “The Dufrenite Problem.” Frondel's work  confirmed that after analysis, the material from the original 1941 find at Greenbelt  was in fact rockbridgeite rather than dufrenite. The article described rockbridgeite as “indistinguishable from dufrenite in its general appearance and confused with that species since earliest times.” Later in the article, Dr. Frondel went even further to refer to rockbridgeite as “identical in appearance with the fibrous varieties of dufrenite.”

Soon thereafter, the U. S. Geological Survey reported x-ray and chemical analyses of a new and unknown species from within Greenbelt concretion material. Subsequently, a new revision in Dana noted that a similar mineral had been found in Russia. A brief description concluded that additional verification was needed.  The new Russian find received the name avovskite.  More than a decade after this Russian discovery and in the midst of the Cold War, Morgan’s article in Rocks and Minerals article noted that “attempt (to obtain more information and/or a sample)  has been made through diplomatic, scientific, and other channels, but no trace of azovskite has been unearthed.”

 Morgan also claimed in his article that “at the very beginning,” he had been promised naming rights from an unnamed source should a  new species be uncovered. He suggested the new mineral be named named fairbanksite  (not to be confused with the lead tellurite fairbankite ) in honor of Dr. Fairbanks. The only reference to fairbanksite we have been able to locate is on Mindat, which describes it as “unidentified microscopic crystals in shrinkage cracks in concretions,” citing Hey’s Chemical Index of Minerals, 2nd Edition 1962.

Even today, the IMA describes the status of azovskite as “doubtful.” Fleischer's Glossary of Mineral Species (2014) does not mention azovskite; nor does either edition of Bernard and Hyrsl's Minerals and their Localities.   Mindat states that azovskite “appears to be a gel” and “may be identical to delvauxite.” Delvauxite, however, is amorphous and is not known to replace crystals of other species,  Still, it is interesting to note brown globular material appearing in shrinkage cracks of Greenbelt concretions that bear a visual resemblance to delvauxite. Delvauxite is not known to have been reported from Maryland.

Catalogued in the Smithsonian collection are numerous “azovskite” specimens, mostly from Greenbelt. The catalog states or implies that none of the specimens was ever x-rayed. A curious and lengthy PDF procured from the Internet describes azovskite as a mixture of  santabarbaraite and goethite.  Also observed on the Internet was an azovskite specimen from Hagendorf, Germany, offered for sale by a European dealer who described it as santabarbaraite and goethite on quartz.  For santabarbaraite to be replacing crystals of goethite hardly seems a stretch. In fact, one of the Greenbelt azovskite specimens catalogued in the Smithsonian collection names goethite as an associated mineral. Santabarbaraite, on the other hand, has never been reported from anywhere in the Americas, much less Maryland. Just as interesting is that the Smithsonian collection catalog gives the Crimean Peninsula as the locality for one of the azovskite specimens.  According to Mindat, the Crimean Peninsula boasts five santabarbaraite localities, far more than any other region or country on earth where santabarbaraite is known to occur.

After  Rocks and Minerals published Mr. Moore’s article in 1965, Dr. Fairbanks submitted his follow-up article entitled “Notes on the unusual mineral locality at Greenbelt Maryland,” In addition to gratefully concurring with Mr. Morgan’s nomenclature  suggestion, Dr. Fairbanks  raised an additional point that 37 years later would prove eerily prophetic. He stated:  

It is definitely odd that the small area in which the rockbridgeite concretions were found was the only one in that area where phosphorous was relatively abundant. A very prominent non-government geologist suggested that a huge dinosaur died here furnishing the phosphorous.  

In 2012,  published  that the well-known local amateur geologist and fossil hunter,  Ray Stanford, was instrumental in the discovery of two nodosaur tracks on the property of Goddard Space Flight Center. A heavily-armored plant eater, the species was known to reach the size of a small elephant. It received its name from the numerous spikes in its armor. Stanford uncovered the tracks during excavation for the new building pictured at left, photographed from the immediately adjacent Goddard Visitors Center. 

The most recent published research regarding the Greenbelt concretions appears in Lawrence R. Bernstein’s 1980 Maryland Geological Survey Publication Minerals of the Washington, D.C. Area, which evolved from an earlier 1975 U.S. Geological Survey Professional Paper (Volume 475, parts 1-4) by Mr. Bernstein. Therein Bernstein noted oral communication from  Mary E Mrose of the U.S. Geological Survey reporting  cacoxenite, lipscombite, phosphosiderite, and strengite in the concretions. Our research turns up no other evidence that lipscombite, phosphosiderite, or strengite were ever reported from Maryland. The same can be said for the beraunite that Morgan claims to have collected between 1944 and 1949.

Hopefully, there are facilities willing to provide further analyses. The possibility of a new mineral species being discovered  in Maryland would surely be significant. Maryland’s only other type locality mineral---for which no type specimen is known to exist---is carrollite, discovered  at the Patapsco Mine in Carroll County and named in 1852. Should analysis of any Greenbelt “azovskite” specimen reveal santabarbaraite, America’s first santamariaite find would similarly be serious mineralogical news.  And confirmed analyses of lipscombite, phosphosiderite, strengite, or beraunite would be a major contribution to what is known of Maryland’s mineralogy.