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, Smithsonian.com  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.   

Sunday, February 21, 2016

In Memorium: Harold Levey: (1925-Feb.8, 2016)


With great sadness we mourn the passing on February 8, of Harold D. Levey  in Baltimore County's Northwest Hospital due to complications from a fall several days earlier. Liked and admired by all who knew him, Harold could be considered the patriarch of Maryland mineral collectors, not only by virtue of his age, but by the breadth of his experience.

Locally, that experience dated from when Baltimore City's Jones Falls pegmatites were accessible and in Baltimore County, both the Bare Hills Copper Mine and the the Bare Hills Chrome Pits yielded rich specimens. He collected also at the McMahon and Texas Quarries in Baltimore County when they were known respectively as the Greenspring Quarry, and the Campbell Quarry. He spent a lot of time at the Fairfax Quarry in Centreville, Virginia, when its management actually permitted overnight camping. The Smithsonian once traded him an African mimetite specimen for a classic Centreville apophyllite on prehnite piece that it prominently exhibited for years.  Harold's local and regional collecting experience contributed to and was later enhanced in 1955 by a six month trip to numerous localities throughout the United States.

Natural history fascinated Harold from when he was a child. While looking for snakes at age 14, he extraneously uncovered the above pictured curved Tourmaline Group (var.) schorl  crystal in quartz. The experience led to his subsequent focus on mineralogy. Curiosity about the find prompted a visit to the Natural History Society of Maryland to seek out someone to identify the specimen. As a result, Harold donated it to the Society’s collection and became active as a member. When Charles Ostrander, NHSM’s  original mineral curator moved to Harford County around 1950 Harold became de facto curator.

It was during this period, when Paul Desautels, then a professor of chemistry at the Maryland State Teacher's College (now Towson State) showed up to view the NHSM collection. That visit led to the formation of the Baltimore Mineral Society. Along with  a small group including  Mr. Desautels and John S. White, both future Curators-in-Charge Gems and Minerals at the Smithsonian,  Harold became a founding member and later  president. 
Harold continued to remain active with the NHSM late into the 1950’s.  NHSM then sponsored a Junior Natural History Society of Maryland. Throughout his life, Harold believed strongly that the best way to perpetuate the hobby of mineralogy was to have youngsters participate. He frequently led field trips for Junior NHSM members to a range of localities. They included visits in Carroll County to the Mineral Hill Mine, as well as a long built over cornfield loaded with quartz crystals near Gamber. He also led more distant trips to the dumps of the Cornwall Iron Mines in Lebanon County, PA, and the Showalter Quarry in Lancaster Co. PA. 

Like so many collectors Harold’s life during late middle age centered on family and work: wife Margie, their daughters Dana and Jodie, and a career as quality control manager for AAI Corporation at Hunt Valley in Baltimore County. Deeply saddened by Margie’s death in 1990, he became less active with mineralogy. However, his interest in minerals remained. He maintained his collection until 2013. That summer, failing health necessitated a move from his home near Pikesville to the nearby North Oaks Retirement Community. 

Further perspective on Harold Levey’s role and stature within the mineralogical community is available at the  Mineralogical Record label Archive:  http://www.minrec.org/labels.asp?colid=598 .



Saturday, January 30, 2016

A Plea to the American Museum of Natural History

Were the images larger, or had we photoshopped them a bit, you could read the labels. Clockwise from far left, they read as follows: Boleite, Cottenite, Cumengite, Laurionite, Diaboleite; and  Matlockite. They are are some of the more aesthetic  systematically classified halides on exhibit in the Amercan Museum of Natural History's Harry Frank Guggenheim Hall of Minerals. While not included on the labels, their localities and chemical composition formulas are shown nearby. With sufficient lighting, that information and the specimens themselves would surely attract a higher level of interest from viewers .

A forum on Mindat entitled "Does anyone else think the AMNH displays are lacking?" spans several pages of opinions, most from well-known and highly respected mineral aficionados. The descriptions include "Dowdy;" Disgraceful;" "A bummer to look at;" "Tragic."  Poor lighting is by far the most frequently mentioned deficiency. 

The lighting is so bad it renders many minerals unrecognizable to the point that they offer little in the way of education or entertainment. Particularly notable in this regard are some of the rarer species present in relatively minor proportion on much larger rocks. Where, for instance, is the whitlockite in the specimen pictured at right? Blown up and brightened with appropriate digital photography software, a milky colorless tabular crystal of about a centimeter in width is visible at top right. It's  an inordinately large crystal for this rare phosphate species. However, insufficient lighting renders the whitlockite invisible. And even with decent lighting, a written description regarding its presence would be necessary for the vast majority of viewers to notice it.

Comments on the Mindat forum offer plenty of opinions as to why the AMNH exhibit is so inadequate. They range from funding issues to bureaucratic red tape. One comment surmised that the AMNH directors disparaged minerals "because they were never alive."

Another recalled the world class mineral collection  that was neglectfully stored away at the Philadelphia Academy and all but forgotten. After many years, the directors of that institution  decided to sell what was left of the collection to  dealers who at least were able to bring the specimens into circulation for people to appreciate.

It is unfortunate that the world class  "Spectacular Stibnite" specimen in a well-lit area outside the the Hall of Minerals beckons those who see it to enter. Upon doing so, they soon observe a large display of mind-blowing native gold specimens from California. The lighting for them is substantial, but fails to present as realistic a visual perspective of these treasures as would a different lighting scheme.  And from here, it all goes downhill.

The AMNH's Financial Statements are available on line along with the names of those on its Board of Trustees. Does anyone on this board appreciate or understand that minerals should be viewed in a manner where it's possible to better appreciate them? If they are to remain in a dark room they might consider for perspective a visit to the the Hillman Hall of Minerals and Gems at the Carnegie Museum of Natural History, or the Cullen Hall of Gems and Minerals at the Houston Museum of Natural History. And should it make sense to light the entire room, they might check out the wonderful Smithsonian Natural History Museum. Something major needs to be done  to remedy the situation.