Saturday, October 31, 2009

Beach Pebble Fun in Marin County

Spending the past few days in San Francisco with a busy schedule, I'd anticipated this would be the first week since launching Mineral Bliss last February that there wouldn't be a post. It was a pleasant family oriented trip, however, into which my son Alex and I were able to squeeze in a few hours for a hike. As we scanned his trail book to pick one, I saw "semi-precious stones" mentioned in conjunction with the "Rodeo Beach Hike." Parking to reach the trail was directly at Rodeo Beach. We drove there and headed out, making it approximately two hundred yards to near the shoreline. Thereafter, we were rarely off our knees.

The picture atop this page is of pebbles ranging in size from about five millimeters to one and a half centimeters. It includes a number of less common pebbles that I'm reluctant to identify without help. Most of what's green is serpentine from the serpentinite rocks abundant in the adjacent Marin County headlands. These headlands are also rich in chert that can be gray, green, red, blue, or brown.
Other beaches along San Francisco Bay yield similar pebbles. Pictured at left are a few that my son Alex picked up several months ago across the Bay at Baker Beach, which is within the San Francisco city limits. I first suspected that the red and brown pebble at center right could be an agate, but am now convinced that it's chert or possibly jasper. One of Marin County's beaches is known as Agate Beach. From the Web, I'm told that many grains of sand there are from agates, but that marine fossils are a better bet for collecting than agate.

Serpentinite pebbles from both Rodeo Beach and Baker Beach remind me of the "jade" that I recall checking out years ago at Jade Beach along the Pacific a couple hundred miles south in the Big Sur. At Jade Beach, the stones are are much larger. Some are actually boulders. They are said to be jadeite and/or nephrite. I'd enjoy the opportunity to compare the Jade Beach material with some of these pebbles.

Saturday, October 24, 2009

The Eight New Minerals Discovered by Pat Haynes

Renowned geologist Pat Haynes wears his cowboy hat in trademark fashion at shows, even since moving from Nevada to Northern Virginia. I didn't ask what was in his left hand when shooting the above picture at the East Coast Gem and Mineral Show in West Springfield, Massachusetts, this past August. However, he usually has with him a directory of approximately 4350 mineral species known to exist. Listings of the approximately 2300 of them in his personal species collection bear checkmarks. Eight of them he discovered himself, nine if you count squawcreekite, which he's quick to inform you that the IMA (International Mineralogical Association) discredited in 2003. He's vocal about his penchant for accurate identification, which can be tricky with the kinds of minerals he's uncovered. Seven have been secondary uranium or vanadium minerals from Colorado and Utah, one an arsenate from New Mexico.

An earlier post at Mineral Bliss featured a title shot of the mineral haynesite. In today's post is an image of a more aesthetically pleasing haynesite specimen, perhaps the best in existence. I had never heard of haynesite until months after meeting Pat at John Veevaert's open house last February in Tucson. He was there hawking micromounts and thumbnail specimens, one of which I recall being plumbophyllite, an IMA approved but yet to published new mineral that someone else discovered. Only months later, enticed to undertake some research after observing a haynesite micromount for sale on eBay, did I learn that Pat Haynes discovered not only haynesite, but seven other new minerals as well.

Beginning with haynesite, they are as follows:

Haynesite: I suspect this could be the best specimen of haynesite ever collected. Pat discovered this uranyl selenite in December of 1986 at the Repete Mine in San Juan County, Utah. Now closed and sealed, the Repete Mine is both the type locality for haynesite and the only locality from which haynesite has ever been reported.

Orthominasragrite: This extremely rare vanadium sulfate accompanied by acicular white rozenite was discovered by Pat in a silicified tree fossil at the North Mesa 5 Mine, Temple Mt., Emery County, Utah. It is the orthorhombic polymorph of minasragrite for which the type locality is the Ragra Mine (minasragra) in Peru. It occurs only in crystalline microscopic crusts.
Anorthominasragrite: Also discovered in a silicified tree fossil at the North Mesa 5 Mine, Temple Mt., Emery County, Utah, anorthominasragrite has mever been reported from any other locality. Anorthominasragrite is the triclinic polymorph of minasragrite. In addition to crystalline microscopic crusts similar to orthominasragrite, anorthominasragrite is also known to form lath-like crystals.
Bobjonesite: Pat insisted that this third vanadium sulfate he discovered at the North Mesa 5 Mine remain in its container to be photographed. Named by Pat to honore the eminent mineralogical speaker and writer, and editor of Rocks and Gems, Bobjonesite is stable only in extremely dry atmosphere and quickly hydrates when exposed to air. Because it has only three waters in its structure as opposed to five waters in the other vanadium sulfates, a synthetic equivalent was used during analysis to determine the x-ray powder diffraction pattern.

Blatonite: One of two minerals Pat Haynes discovered in the mid 1990's at the Jomac Uranium Mine, Brown's Rim, San Juan County, Utah, the only locality from which blatonite has ever been reported. An uranyl carbonate (monohydrate), it occurs exclusively in acicular crystals as shown . The name blatonite honors the Belgian crystallographer Norbert Blaton.
Oswaldpeetersite: Another uranyl carbonate found exclusively at the Jomac Uranium Mine, it is named after Belgian crystallographer and uranium mineralogy researcher Maurice Oswald Peters. Oswaldpeetersite is the first known basic uranyl carbonate without additional cations (positive ions) in its structure.

Metamunirite: Discovered by Pat in 1986 at the Burro Mine, Slick Rock, San Miguel County Colorado, this anydrous sodium metavanadate is named for its relationship to munirite and is a product of munirite dehydration. Extremely rare, it most commonly occurs as post-mining efflorescent crusts.

Maxwellite: In 1983, thinking that he had been collecting durangite at the Squaw Creek Tin Mine in Catron County, New Mexico, Pat later learned that what he'd picked up was a new mineral species. The iron analog of durangite, this fluoro sodium iron arsenate, is named for the late Charles Henry Maxwell, a U.S. Geological Survey geologist renowned for his work in New Mexico.

Squawcreekite: Pat uncovered this iron antimony oxide in 1983 at the Squaw Creek Tin Mine at about the same time he discovered maxwellite. In 1991 the IMA approved it as the new mineral squawcreekite. They later discredited it in 2003 as a tin-rich triphuyite. MINDAT refers to squawcreekite as a synonym of triphuyite.

Saturday, October 17, 2009

The 2010 Micromineral Micromount Calendar

Calendars featuring minerals are somewhat obscure. Mineral calendars that feature microminerals are very obscure. Regardless, microminerals are typically prone to more beauty and detail than any other part of the mineral kingdom. For that matter many of the most spectacular species in existence require substantial magnification to be seen. Below are the choices for this year's calendar.

Every page is on sturdy cover weight matte coated stock. Pages measures 8 1/2 x 11 inches closed and 11 x 17 inches open. A very limited number are available at the eBay Store link at the top right of this page. If they sell out quickly enough, more will be printed. If not, they wont.

Saturday, October 10, 2009

Mineral Mastery at an Early Age

Listed below are some of the mineralogical coups credited to 11 year old Jessica of Western Maryland.

  • A link to her photographically illustrated review of the East Coast Gem and Mineral Show is featured on the cover page of Mindat.

  • An exhibit at the Gemcutters Guild gem and Mineral Show in September was a display she assembled of selected minerals from her collection.

  • She has been asked to put together a display of her minerals on the floor of the Tucson Convention Center for the four day "Main" Tucson Gem and Mineral Show, Feb. 11-14, 2010.

  • By special invitation, she spent a day in the mineralogy lab at Penn State working with the scm microscope and "crystal maker" apparatus. The X-ray diffraction scope had broken the day she was there.

  • At the Smithsonian Museum of Natural History she rated a special behind the scenes visit that included entry to its legendary and highly secure "Blue Room" vault.

  • I finally got to meet Jessica and her dad Bob this past weekend at the 53rd annual Desautels Micromount Symposium where she was an active participant amidst numerous international Micromount Hall of Famers and at least two mineralogists who have discovered new minerals and after whom minerals have been named.

This young lady's prodigious quest for mineralogical knowledge (and minerals, of course) traces to a visit with her parents to the Catoctin Zoo when she was two years old. More than the animals, what fascinated her most that day was a granite pebble that she picked up in which was a grain of pyrite. Thenceforth, she became an aficionado of "pretty stones." The interest in identifying them and the related scientific components began about two years ago.

Her father has been with her every step of the way. Together, they take on at least two serious mineral excursions every month, including shows and localities. Among the latter have been the dumps of the Mineral Hill Mine in Carroll County; those of the Allah Cooper Mine in Mineral, Virginia; the Tripp Mine in New Hampshire; and the Jacobs Geode Mine in Missouri. Her "big wish" would be to "get into more localities."

Jessica is an enormous exception to a disturbing trend in mineralogical circles of diminished younger generation enthusiasm for minerals, or for that matter natural history in general. She confirmed to me that interest in minerals is practically nonexistent in her age group and that the handful of young enthusiasts she's met through club circles are a few years older.

Will Jessica's love and fascination for the hobby last? No one is saying. I asked her if she had yet found a "niche." She confessed she hadn't. Rather, by virtue of her age, her engagement with the hobby, and the dearth of others like her, Jessica exemplifies about as important and significant a niche as exists in mineralogy.

Saturday, October 3, 2009

Word from Harvard about Bare Hills Chromite and Magnetite

A month ago, Mineral Bliss posted observations related to Maryland minerals at the Harvard Mineralogical Museum. Of particular interest was a small exhibit of chromite in various habits from different localities. Two of the selections were from Bare Hills in Baltimore County. One was massive chromite with fibrous serpentine. The other was the glass vial pictured above at center filled with minute octahedra about which my comments were as follows:

I would love to know how these crystals were collected. Did they occur as floaters in the soil, or were they extracted from a (presumably serpentinite) matrix? Although massive chromite has always been ubiquitous at the Bare Hills serpentine barrens, crystals are most unexpected.

That expression of curiosity would have been the end of it had not my friend Harold Levey (at left) telephoned to share further thoughts. To Harold, whose collecting experience at Bare Hills spans more than 70 years, the likelihood of chromite crystals having been collected at Bare Hills was every bit as remote. He also emphasized the visual resemblance of the crystals in the jar to magnetite crystals that were ubiquitous on the long built over dumps of the Bare Hills Copper Mine.

Still in my possession are the magnetite crystals pictured at left of the jar that I collected at the Bare Hills Copper Mine myself more than 50 years ago. They typically occurred as pictured in a talc-like steatite soft enough for one's fingernails to dislodge. In appearance they resemble chromite crystals. Pictured at right of the jar is the only example immediately available for me to photograph of crystalized chromite (a micromount from Gabon, actually) . MINDAT has numerous better examples.

I was wary of challenging the identification of anything displayed in such a world class museum. However, encouraged by Harold to do so, I mailed off a letter to its curator, Dr Carl Francis suggesting the possibililty of a discrepancy.

Just two weeks later, a return letter arrived from Dr. Francis. He had researched the history of the specimen and even found its original label from the Leonhard Liebener Collection, which was
purchased in Austria in 1869. While the information on the exhibit label had been correctly transcribed, the crystals, when confronted with a magnet, were mostly magnetic octahedra accompanied by "some rounded black, nonmagnetic (chromite?) grains. " I conclude," Dr. Francis wrote," that the specimen is a mixture that was accepted as chromite by Liebener and hasn't been questioned until your recent visit. I have relabeled it magnetite, attributed it to the Bare Hills Copper Mine on your authority, and retired it from the display."

Thank you Dr. Francis for going to such lengths upon hearing from the likes of Yours Truly, and thank you Harold Levey for the observation that inspired in me the gall to write. As a bonus, Dr. Francis shared additional information about Maryland Minerals owned by the Harvard Museum that are not currently on display. We're hoping for the opportunity to share related information in the coming months.