Baltimore, Maryland lost its premier mineral dealer and a lot more with the June 2 passing of Larry Krause. Just about every local collector was both a customer and a friend. Dealing minerals was only one of the many hats Larry wore. Most of them extended far beyond the interests that bind us mineral people together. Regardless of the hat he was wearing, what most lingers in the memory is of Larry himself and the spirit that drove him. He was gentle, kind, opinionated, motivated by challenges, driven by ethics, civic-minded, cultural minded, good-humoured, and he had a great marriage.
Larry and I go back nearly 33 years, most of which had nothing to do with minerals. My earliest memory is when he as publisher and Alice as editor---they would marry five years later---engaged me as a writer for the Baltimore Chronicle. We spent many hours together over weeks, months, perhaps even a year before Larry mentioned that he collected minerals, which had been my hobby as a child. Soon thereafter, he took me to collect iridescent siderite at Arbutus Canyon along Washington Boulevard (long since paved over by Home Depot). As enjoyable as the experience was for me, a lifestyle encompassing two jobs, two children, and two acres precluded me from resuming this hobby that had been all but forgotten for 25 years.
Larry had a lot of other responsibilities as well during this period. They included publishing at least five community newspapers, two magazines, and a book. He also founded two nonprofits, and had prominent roles with more than several other organizations, among them the Baltimore Mineral Society, which he served at various junctures as secretary, vice president and president.
I stayed in touch with Larry, writing for four of his publications and serving on the boards of directors of two of them. In 1989, I began writing a weekly column entitled "Jake About Town" for the Chronicle. It related to everything that was offbeat about Baltimore's culinary scene.
"Jake About Town" became so much a part of my life that in 1992, I sold the home service brokering business which had been my livelihood for 21 years and launched a company to produce a line of extremely exotic canned soups. Though the soup business never made me rich, it replaced the worries associated with responsibility for thousands of jobs taking place in peoples' houses every year with a level of happiness and a sense of fulfillment I'd never before known. Were it not for Larry, this probably never would have happened, and I mention it only because of the role he played in getting me back into minerals, which became the next chapter.
During the final decade of his life, Larry gradually transitioned from publishing community newspapers to devoting more time to his mineral collection and Octahedron Minerals, the sideline business started years before. It wasn't long before the enormous two-room basement of his and Alice's house was filled with minerals from floor to ceiling. His personal collection was in one of the rooms, Octahedron's inventory in the other.
Around the time I sold the soup business in 2004, to earn more money in real estate and start thinking about retirement, Larry invited me to accompany him to a meeting of the Baltimore Mineral Society and encouraged me to purchase some minerals from him. By this time, I was telling people that minerals were "something to pursue when I get older." Though my life continued to be crammed with other commitments, Larry had soon sold me enough minerals to justify creating a space in the basement to display them. Shortly thereafter, the childhood passion that 45 years before had given way to sports, girls, and other adolescent distractions reinstated itself full force.
After learning that he had cancer, Larry began to sell off in earnest the inventory of Octahedron Minerals as well as his collection. He did so mostly by inviting specific collectors, usually in small groups, to come to the house and shop. Though receiving more than my share of invitations, and wanting to be there, I was out of town on most of these occasions, but recall all too clearly the one that I resisted. Our house already had more rocks in it than we had appropriate space for, and I wanted to see more of them moving out---a slow and tedious process when selling them on line---than coming in. How secondary that concern proved to be when realizing now the opportunity I missed to have had just a little more time hanging out with Larry.
Wednesday, June 23, 2010
Saturday, June 19, 2010
An All But Forgotten Maryland Gypsum Find
Among the most spectacular mineral specimens known to have been collected in Maryland are the blades and rosettes of gypsum (referred to as selenite when crystallized) that have been plucked from clay along the St. Mary's River banks at Chancellors Point and at Fort Washington in Prince Georges County beneath the bluffs of the Potomac. Lesser known, arguably more spectacular, and all but forgotten are crystals collected approximately 50 years ago from a deposit near Fort Foote in Prince Georges County about three miles down river from Fort Washington. For the second recent Sunday afternoon, a row, I had the opportunity to accompany Jeff Nagy on another drive to Virginia, this time to Strasburg for further research on his project to update and republish the 1981 Maryland Geological Survey publication Minerals of the Washington, DC Area by Lawrence Bernstein. Specifically, his mission was to meet and learn about the find from Gary Allard, who with his brother Brian, now deceased, had discovered the deposit.
For its year and a half of productivity, the site was the secret domain the two brothers. Gary appears in our title picture holding a rosette and the most spectacular crystal blade of the find, which is the largest crystal of selenite I've ever seen from Maryland. Amazingly, its appearance suggests that it could once have been part of a rosette. It is the same crystal that Gary was photographed holding 49 years ago in an article entitled Crystals by the Ditchful that appeared in the June-July, 1961 edition of Rocks and Minerals . At present, we are awaiting permission from Rocks and Minerals new publisher to post a reproduction of that earlier picture. If granted, one will be inserted herein soon thereafter.
Over less than two years, the two brothers pretty much cleaned out most of the crystals, using some for a science project at school and selling a others to classmates. Then they notified Ellsworth Swift,who authored the article in Rocks and Minerals. By then, the ditch had become less a source of crystals than what Swift referred to as "a challenge to discover the nature of the deposit and a chance to speculate on its formation."
He noted in the article that the Fort Foote crystals occurred in the Patapsco Clay, which also hosted other gypsum finds reported from the region. He described this clay as formed in the Cretaceous Age and variegated (in colour). Gary Allard recalled that the crystals occurred in a a "purplish" clay that was darker than the crystal bearing Patapsco clay at nearby Fort Washington. The crystals that Gary and Brian collected, whether rosettes or single crystals, were generally larger and less stained by clay than most of the better known material collected at Fort Washington and in St. Mary's County.
Particularly interesting was that while riverside bluffs had yielded the Fort Washington and St. Mary's crystals, those from Fort Foote were collected about a half mile inland in a ditch intended for drainage alongside what was soon to be paved over as an extension of River Bend Road. Just as noteworthy was their confinement to a 125 foot section of the ditch. Swift suggested that this could mean the crystals "concentrated along structural features such as joints," or that this particular deposit was "irregular in shape with the ditch merely cutting a cross section through the crystal patch.'" He explained further how the crystals were most likely formed when groundwater from the Piedmont that contained sulfuric acid from decomposing pyrite flowed eastward and mixed with the lime bearing beds of the Coastal Plain at Fort Foote.
Gary Allard now lives in the Shenandoah Valley near Strasburg, Virginia. He said he moved there because it had more kinds of rocks than than "that boring Coastal Plain" where he grew up." He still loves to collect minerals and prior to his recent retirement was a jeweler and metal engraver. One of his recent finds that amazed Jeff and me was the green quartz crystal pictured at right from near Front Royal in Warren County, Virginia. The book Minerals of Virginia, by R.V Dietrich, 1991, noted nothing like it from Warren County. The only green quartz the book mentioned was presumably massive and from another part of Virginia with coloration "probably due to included amphibole or chlorite." It too, Gary discovered along the side of a dirt road albeit not in a ditch.
For its year and a half of productivity, the site was the secret domain the two brothers. Gary appears in our title picture holding a rosette and the most spectacular crystal blade of the find, which is the largest crystal of selenite I've ever seen from Maryland. Amazingly, its appearance suggests that it could once have been part of a rosette. It is the same crystal that Gary was photographed holding 49 years ago in an article entitled Crystals by the Ditchful that appeared in the June-July, 1961 edition of Rocks and Minerals . At present, we are awaiting permission from Rocks and Minerals new publisher to post a reproduction of that earlier picture. If granted, one will be inserted herein soon thereafter.
Over less than two years, the two brothers pretty much cleaned out most of the crystals, using some for a science project at school and selling a others to classmates. Then they notified Ellsworth Swift,who authored the article in Rocks and Minerals. By then, the ditch had become less a source of crystals than what Swift referred to as "a challenge to discover the nature of the deposit and a chance to speculate on its formation."
He noted in the article that the Fort Foote crystals occurred in the Patapsco Clay, which also hosted other gypsum finds reported from the region. He described this clay as formed in the Cretaceous Age and variegated (in colour). Gary Allard recalled that the crystals occurred in a a "purplish" clay that was darker than the crystal bearing Patapsco clay at nearby Fort Washington. The crystals that Gary and Brian collected, whether rosettes or single crystals, were generally larger and less stained by clay than most of the better known material collected at Fort Washington and in St. Mary's County.
Particularly interesting was that while riverside bluffs had yielded the Fort Washington and St. Mary's crystals, those from Fort Foote were collected about a half mile inland in a ditch intended for drainage alongside what was soon to be paved over as an extension of River Bend Road. Just as noteworthy was their confinement to a 125 foot section of the ditch. Swift suggested that this could mean the crystals "concentrated along structural features such as joints," or that this particular deposit was "irregular in shape with the ditch merely cutting a cross section through the crystal patch.'" He explained further how the crystals were most likely formed when groundwater from the Piedmont that contained sulfuric acid from decomposing pyrite flowed eastward and mixed with the lime bearing beds of the Coastal Plain at Fort Foote.
Gary Allard now lives in the Shenandoah Valley near Strasburg, Virginia. He said he moved there because it had more kinds of rocks than than "that boring Coastal Plain" where he grew up." He still loves to collect minerals and prior to his recent retirement was a jeweler and metal engraver. One of his recent finds that amazed Jeff and me was the green quartz crystal pictured at right from near Front Royal in Warren County, Virginia. The book Minerals of Virginia, by R.V Dietrich, 1991, noted nothing like it from Warren County. The only green quartz the book mentioned was presumably massive and from another part of Virginia with coloration "probably due to included amphibole or chlorite." It too, Gary discovered along the side of a dirt road albeit not in a ditch.
Monday, June 14, 2010
Collecting at the Havre de Grace Quarry
Hats off to the Vulcan Materials Company/Arundel Corporation, except for hard hats that is. Assistant Plant Manager Patrick Pieton couldn't have been more gracious when he opened up the Havre de Grace Quarry on a recent Saturday for Baltimore Mineral Society members to collect.
The quarry descends from 670 acres immediately south of the Susquehanna River and west of Havre de Grace at a point where the Port Deposit gneiss meets Harford County's metagabbro and amphibolite. It is visible off to the right as one drives north across the Susquehanna on I-95. Although the rocks are hard, they bear plenty of mineral specimens that are relatively easy to collect.
After an informative briefing from Pat about the quarry and mine safety, we followed him in our cars down several levels to collect along berms on either side of road. Sulphides proved to be abundant in the rocks here, especially pyrite in large masses and sometimes in cubes up to at least an inch. Unfortunately these crystals were impossible to extract from the much harder gneiss and metagabbro encasing them. Often associated with the pyrite were less sizeable masses of bright yellow golden chalcopyrite sometimes accompanied by wildly iridescent bornite. One of the more interesting finds was a sizeable mass of pyrrohotite running through a matrix bearing few small particles of what through the loupe appeared to be crystalline sphalerite.
Excitement increased when Fred Parker found a large boulder partially coated with a druse of clear colorless zeolites. Through the loupe, we were able to identify heulandite for sure, and very possibly some chabazite as well. The druse, however, was of a different hue than a particularly attractive 1988 heulandite find by Parker where the micro crystals were orangish brown and occasionally accompanied by slightly larger crystals of white calcite.
Collecting only got better when Pat reappeared to lead us to the bottom level of the quarry. Within minutes we were in the midst of numerous rocks coated with heulandite druses of similar hue to those from the 1988 find. Although mostly quite weathered, occasional scatterings of micro pyrite cubes contributed a dramatic sparkle to some of them. The image at right was shot at 40x.
The quarry descends from 670 acres immediately south of the Susquehanna River and west of Havre de Grace at a point where the Port Deposit gneiss meets Harford County's metagabbro and amphibolite. It is visible off to the right as one drives north across the Susquehanna on I-95. Although the rocks are hard, they bear plenty of mineral specimens that are relatively easy to collect.
After an informative briefing from Pat about the quarry and mine safety, we followed him in our cars down several levels to collect along berms on either side of road. Sulphides proved to be abundant in the rocks here, especially pyrite in large masses and sometimes in cubes up to at least an inch. Unfortunately these crystals were impossible to extract from the much harder gneiss and metagabbro encasing them. Often associated with the pyrite were less sizeable masses of bright yellow golden chalcopyrite sometimes accompanied by wildly iridescent bornite. One of the more interesting finds was a sizeable mass of pyrrohotite running through a matrix bearing few small particles of what through the loupe appeared to be crystalline sphalerite.
Excitement increased when Fred Parker found a large boulder partially coated with a druse of clear colorless zeolites. Through the loupe, we were able to identify heulandite for sure, and very possibly some chabazite as well. The druse, however, was of a different hue than a particularly attractive 1988 heulandite find by Parker where the micro crystals were orangish brown and occasionally accompanied by slightly larger crystals of white calcite.
Collecting only got better when Pat reappeared to lead us to the bottom level of the quarry. Within minutes we were in the midst of numerous rocks coated with heulandite druses of similar hue to those from the 1988 find. Although mostly quite weathered, occasional scatterings of micro pyrite cubes contributed a dramatic sparkle to some of them. The image at right was shot at 40x.
Also present at the same spot were some rocks covered with bladed sprays of white laumontite. After whacking one of them with my mallet, two attractive small cabinet sized slabs broke off to expose laumontite on both sides. Nearby, Bob Eberle pounded away at a boulder from which he ultimately extracted an attractive epidote crystal of approximately an inch. As abundant as epidote is likely to be in this kind of rock, it was the only such find of the day.
As our noon deadline approached, Fred Parker wondered off to what was probably the day's piece de resistance. Quite apart from where we'd been collecting, it was an enormous boulder he'd spotted soon after our arrival at the bottom level. The druses of orange heulandite covering it were less weathered. After pounding away at the boulder with a sledge hammer he inserted a small chisel at a point where one crystal coated slab after another soon detatched. As he wrapped the pieces in newspaper and placed them into a compartmentalized flat, several of us ran off in yet another direction from the spot where we'd spent nearly all of the past two hours. Almost too much heulandite, it seemed, not enough time.
Sunday, June 6, 2010
Northern Virginia Then and Now
The two Centreville Quarry apophyllite on prehnite specimens at left are displayed at the Smithsonian. Those at right are from the collection of a Northern Virginia resident who has been prospecting in the area for more than half a century. While the pieces from the Smithsonian are better known, all are classics specimens from a classic locality. On Lee Highway less than 30 miles from the Smithsonian, the Centreville Quarry is home turf.
On a spur of the moment visit to Washington, D.C. last week, I had dropped by the Smithsonian while my wife accompanied her cousin, who was visiting from Texas, took in the Mall on a tour bus. The only minerals I took time to photograph were the two apophyllite and prehnite specimens at top left. My purpose was to show them to my friend Harold Levey, who in the good old days circa 1950 had permission to camp out at the Centreville quarry and scarf up such material to his heart's content. Harold and his buddies once showed up at the Smithsonian with a particularly attractive specimen and cut a deal with then Curator of Minerals George Switzer to exchange it for a duplicate mimetite specimen from its Robeling Collection. Their Centreville Quarry find quickly found a home in a prominent area of the mineral gallery, which in those days was in a different part of the Museum of Natural History Building. Needless to say, much has changed over 60 years both at the Smithsonian and the former mineral collecting environs of Northern Virginia.
As synchronicity would have it, two days later I found myself at the Falls Church home of the collector who owned the equally if not more impressive specimens pictured at top right. My original plan for that day had been to check out the site of a long forgotten 1960's gypsum find with Jeff Nagy for his project to update and revise the 1980 Maryland Geological Survey publication Minerals of the Washington, D.C. Area by Lawrence R. Bernstein. After those arrangements were postponed, Jeff had arranged instead for us to visit a source whom the original publication had credited with "oral communications" relating to several noteworthy Northern Virginia finds from quite far off the beaten track. He was also the owner of those other two classic apophyllites on prehnite.
While providing us with extensive input that was both timely and informative, he also shared fascinating details relating to the "outside the box" journey that led to his encyclopedic knowledge about the geology, mineralogy, paleontology, and archaeology of Northern Virginia as well as owning some of the finest mineral specimens the region ever produced. His request for anonymity helped me stay focused on the material at hand.
In addition to the apophyllite and prehnite specimens that I was able to photograph, his collection included the most spectacular stilbite crystals I've ever seen from Virginia as well as an amazing byssolite specimen needing to be seen to be believed. Like the apophyllites on prehnite, both of these specimens were also collected years ago at the Centreville Quarry. Since their locations in the cabinet were not conducive to photographs that would do them justice and because of time and space constraints, we agreed that they would be photographed on a subsequent visit.
Most of the collecting in Northern Virginia is now limited to those rare occasions when by special arrangement, a couple of quarries long past their collecting primes permit mineral societies to visit on field trips. Otherwise, little remains accessible beyond stream beds and their cobbles. Our host collected the ilmenite specimen at left, which is by far the largest specimen I've ever observed from the United States, from such a deposit just a few yards from Military Road. He also showed us no less impressive a treasure from another stream bed deposit in Holmes Run. It was a perfectly terminated and barely tumbled three inch by two inch amethyst crystal. We surmised that perhaps it had weathered relatively recently from a nearby matrix and probably become buried soon thereafter.
On a spur of the moment visit to Washington, D.C. last week, I had dropped by the Smithsonian while my wife accompanied her cousin, who was visiting from Texas, took in the Mall on a tour bus. The only minerals I took time to photograph were the two apophyllite and prehnite specimens at top left. My purpose was to show them to my friend Harold Levey, who in the good old days circa 1950 had permission to camp out at the Centreville quarry and scarf up such material to his heart's content. Harold and his buddies once showed up at the Smithsonian with a particularly attractive specimen and cut a deal with then Curator of Minerals George Switzer to exchange it for a duplicate mimetite specimen from its Robeling Collection. Their Centreville Quarry find quickly found a home in a prominent area of the mineral gallery, which in those days was in a different part of the Museum of Natural History Building. Needless to say, much has changed over 60 years both at the Smithsonian and the former mineral collecting environs of Northern Virginia.
As synchronicity would have it, two days later I found myself at the Falls Church home of the collector who owned the equally if not more impressive specimens pictured at top right. My original plan for that day had been to check out the site of a long forgotten 1960's gypsum find with Jeff Nagy for his project to update and revise the 1980 Maryland Geological Survey publication Minerals of the Washington, D.C. Area by Lawrence R. Bernstein. After those arrangements were postponed, Jeff had arranged instead for us to visit a source whom the original publication had credited with "oral communications" relating to several noteworthy Northern Virginia finds from quite far off the beaten track. He was also the owner of those other two classic apophyllites on prehnite.
While providing us with extensive input that was both timely and informative, he also shared fascinating details relating to the "outside the box" journey that led to his encyclopedic knowledge about the geology, mineralogy, paleontology, and archaeology of Northern Virginia as well as owning some of the finest mineral specimens the region ever produced. His request for anonymity helped me stay focused on the material at hand.
In addition to the apophyllite and prehnite specimens that I was able to photograph, his collection included the most spectacular stilbite crystals I've ever seen from Virginia as well as an amazing byssolite specimen needing to be seen to be believed. Like the apophyllites on prehnite, both of these specimens were also collected years ago at the Centreville Quarry. Since their locations in the cabinet were not conducive to photographs that would do them justice and because of time and space constraints, we agreed that they would be photographed on a subsequent visit.
Most of the collecting in Northern Virginia is now limited to those rare occasions when by special arrangement, a couple of quarries long past their collecting primes permit mineral societies to visit on field trips. Otherwise, little remains accessible beyond stream beds and their cobbles. Our host collected the ilmenite specimen at left, which is by far the largest specimen I've ever observed from the United States, from such a deposit just a few yards from Military Road. He also showed us no less impressive a treasure from another stream bed deposit in Holmes Run. It was a perfectly terminated and barely tumbled three inch by two inch amethyst crystal. We surmised that perhaps it had weathered relatively recently from a nearby matrix and probably become buried soon thereafter.
In coming weeks, Jeff Nagy will be prospecting such stream beds and what few other Northern Virginia collecting spots of which any trace remains. Once published, his revision of Minerals of the Washington, D.C. Area will bring its readers up to the moment.
Tuesday, June 1, 2010
Deweylite Confusion
How I wish the Maryland Academy of Sciences still maintained its display of Maryland minerals on the third (or fourth) floor of Baltimore's Enoch Pratt Free Library. That was several decades before the Academy's move in 1980 to its Inner Harbor domicile, which to the best of my knowledge has yet to house any minerals from Maryland or anywhere else.
Right next to an enormous Montgomery County gold nugget embedded in a quartz boulder was an humongous chunk of Bare Hills deweylite that oddly enough fascinated me equally as much. Three closeup images of lesser Baltimore County deweylite pieces from my personal collection compose the title picture for this post. From left to right, their localities are the Bare Hills serpentine barrens along Falls Road less than a mile north of the city line, the former Dyer Quarry at Soldiers Delight, and the still active Blue Mount Trap Quarry north of Monkton. Wherever it is found, deweylite is never a species, but a combination of species that seem to vary not only from locality to locality, but according to whom you ask. All that appears to be certain is that serpentine is part of the equation.
The image at left graced the Maryland Minerals web site slide show until about a month ago. It disappeared pursuant to a lesson learned from John S. White, one that seemed to me a bit arcane for mention in our previous post. Even John's advice struck me as a bit convoluted at first, though ultimately it proved to be more concise than anything my subsequent research could uncover. "The best approach," he suggested, " is probably to label it Serpentine "Deweylite."'
Bernard and Hyrsl's Minerals and Their Localities lists Deweylite in italics with the following description: "Deweylite, synonym gymnite----A mixture of serpentine, stevensite or talc minerals, fine grained, yellow, green , red. As resinous crusts in serpentinites at-----(several localities). " Mindat refers to deweylite as "a mixture of various poorly ordered trioctahedral 1:1 and 2:1 layer silicates, mainly lizardite and stevensite. Mindat describes gymnite as both a synonym for antigorite and also an "obsolete name for an apparently amorphous antigorite," and it describes lizardite as a species "closely related to" antigorite and also chrysotile." Antigorite, lizardite, and chrysotile are all prominent members of the serpentine group.
A third definition of "gymnite" from Webster's Dictionary on the Internet proved to be the most interesting part of my research, referring to it as a "hydrous silicate of magnesium coming from Bare Hills, Maryland." Since Minerals and their Localities defines gymnite as a synonym for deweylite itself, and Mindat refers to it as a synonym for antigorite, a reasonable conclusion would be that antigorite is a major component of deweylite from Bare Hills. While our photographs of deweylite from Bare Hills (as well as two other Baltimore County localities) depict antigorite with a brownish colour that might appear far from typical, the species occurs in numerous colors, can range from fibrous to nodular, and has been referred to by a variety of names including , picrolite, and baltimorite. As for other species in the deweylite mix, a magnesite presence is obvious in each of the three Baltimore County specimens.
On the other hand, I've never encountered mention of lizardite from any of deweylite's three Baltimore County localities. At other localities reporting deweylite where lizardite is known to occur, I'd assume that the combination of species could be different. At least John S. White managed to keep things simple. Our Bare Hills "deweylite" image will soon reappear at Maryland Minerals web site with the label that he suggested: Serpentine "Deweylite."
Right next to an enormous Montgomery County gold nugget embedded in a quartz boulder was an humongous chunk of Bare Hills deweylite that oddly enough fascinated me equally as much. Three closeup images of lesser Baltimore County deweylite pieces from my personal collection compose the title picture for this post. From left to right, their localities are the Bare Hills serpentine barrens along Falls Road less than a mile north of the city line, the former Dyer Quarry at Soldiers Delight, and the still active Blue Mount Trap Quarry north of Monkton. Wherever it is found, deweylite is never a species, but a combination of species that seem to vary not only from locality to locality, but according to whom you ask. All that appears to be certain is that serpentine is part of the equation.
The image at left graced the Maryland Minerals web site slide show until about a month ago. It disappeared pursuant to a lesson learned from John S. White, one that seemed to me a bit arcane for mention in our previous post. Even John's advice struck me as a bit convoluted at first, though ultimately it proved to be more concise than anything my subsequent research could uncover. "The best approach," he suggested, " is probably to label it Serpentine "Deweylite."'
Bernard and Hyrsl's Minerals and Their Localities lists Deweylite in italics with the following description: "Deweylite, synonym gymnite----A mixture of serpentine, stevensite or talc minerals, fine grained, yellow, green , red. As resinous crusts in serpentinites at-----(several localities). " Mindat refers to deweylite as "a mixture of various poorly ordered trioctahedral 1:1 and 2:1 layer silicates, mainly lizardite and stevensite. Mindat describes gymnite as both a synonym for antigorite and also an "obsolete name for an apparently amorphous antigorite," and it describes lizardite as a species "closely related to" antigorite and also chrysotile." Antigorite, lizardite, and chrysotile are all prominent members of the serpentine group.
A third definition of "gymnite" from Webster's Dictionary on the Internet proved to be the most interesting part of my research, referring to it as a "hydrous silicate of magnesium coming from Bare Hills, Maryland." Since Minerals and their Localities defines gymnite as a synonym for deweylite itself, and Mindat refers to it as a synonym for antigorite, a reasonable conclusion would be that antigorite is a major component of deweylite from Bare Hills. While our photographs of deweylite from Bare Hills (as well as two other Baltimore County localities) depict antigorite with a brownish colour that might appear far from typical, the species occurs in numerous colors, can range from fibrous to nodular, and has been referred to by a variety of names including , picrolite, and baltimorite. As for other species in the deweylite mix, a magnesite presence is obvious in each of the three Baltimore County specimens.
On the other hand, I've never encountered mention of lizardite from any of deweylite's three Baltimore County localities. At other localities reporting deweylite where lizardite is known to occur, I'd assume that the combination of species could be different. At least John S. White managed to keep things simple. Our Bare Hills "deweylite" image will soon reappear at Maryland Minerals web site with the label that he suggested: Serpentine "Deweylite."
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