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September 2018 Bulletin of the New York Mineralogical Club, Inc The BULLETIN OF THE NEW YORK MINERALOGICAL CLUB, INC Volume 132 No. 9 September 2018 PETER KELEMEN HAWAIIAN GEMSTONE RAIN Art of Orra White Hitchcock MOON MOGANITE See page 11! BLUE DIAMOND SOURCES SPHALERITE BANQUET RESERVATION FORM America’s Oldest Gem & Mineral Club Founded 1886 Incorporated 1937 Bulletin of the New York Mineralogical Club Founded 1886 Ë New York City, New York Ë Incorporated 1937 Volume 132, No. 9 America’s Oldest Mineral & Gem Club September 2018 September 5th Meeting: Dr. Peter B. Kelemen: “Carbon Carnelian (& Halloween) Theme Mineralization in Peridotite” Featured at 2018 Annual Banquet The rocks in Oman are special, says Dr. Peter B. Kelemen. They remove planet- By Mitch Portnoy Banquet Gifts warming carbon dioxide from the air and This year’s banquet, which is taking Banquet Games & Prizes turn it to stone. In theory, these rocks could place on Wednesday, October 17, 2018 at Video Entertainments store hundreds of years of human emissions the Watson Hotel, will center on the theme Banquet Song Special Note Card Sets of CO2. of “Carnelian” (but also have a hint of Halloween). Silent Auction Offerings Other Surprises! The registration form for this year’s banquet can be found on page 12 in this Peter and other scientists say that if this issue. Get it to me as soon as possible – it natural process, called carbon helps enormously in the event planning. mineralization, could be harnessed, See you at the banquet! accelerated and applied inexpensively on a huge scale — admittedly some very big “ifs” — it could help fight climate change. Rocks could remove some of the In the past, the banquet’s gemstone billions of tons of heat-trapping carbon themes have included colored diamonds dioxide that humans have pumped into the (2011), tanzanite (2012), jade (2013), ruby air since the beginning of the Industrial (2014), garnet (2015), opal (2016) and most Age. recently, amethyst (2017). And by turning that CO2 into stone, the rocks in Oman — or in a number of other places around the world that have similar geological formations — would ensure that the gas stayed out of the atmosphere Issue Highlights forever. Peter B. Kelemen is the Arthur D. President’s Message . 2 Storke Memorial Professor, Department of Meeting Minutes. 2 Earth and Environmental Sciences, Blue Diamond Sources. 3 Columbia University. His geological Hawaiian Gemstone “Rain” . 4 interests are wide and his writings prolific. Moon Moganite. 5 Peter last spoke to the NYMC in May Killing Watches . 6 of 2006 about steep terrain mineral Yellowcake Uranium . 6 exploration. We are glad to have him back! Medieval Birthstones . 7 As a result, you can expect to see All are encouraged to attend this Topics in Gemology: Sphalerite. 10 orange carnelian galore in the: meeting and hear Peter’s talk about this The Art of Orra White Hitchcock. 11 Room Decorations extremely relevant and timely topic. This is Banquet ‘18 Reservation Form . 12 Banquet Posters & Banners surly a presentation not to be missed! Club & Show Calendars. 13 Food & Drink Table Centerpieces 2 Bulletin of the New York Mineralogical Club, Inc. September 2018 President’s Message Club Meeting “Minutes” for Members in the News By Mitch Portnoy August 5, 2018 Joseph A. Freilich, controversial By Vivien Gornitz, Secretary mineral collector and dealer, passed October Banquet RSVP Attendance: 30+ away in June 2018. Joe was our banquet You will find the 2018 banquet reservation Location: Upper West Side, NYC speaker on November 8, 2000. form on page 12 of this issue. I IMPLORE President Mitch Portnoy “presided” The Speaker-in-Residence for the fall you to get your banquet forms or at least Announcements: Wildacres session will be noted member your RSVP’s in to us. Knowing the All Special Sale attendees received an Alfredo Petrov. attendance count is extremely important to Arizona glauberite pseudomorph: Demetrius Pohl (past president) co- everyone involved in making this event run authored an article about a mine in the smoothly. If you do not tell us you are Congo Republic in the July/August 2018 coming, you will lose the subsidy provided Mineralogical Record; the late Larry by the Club and have to pay full price at Conklin was mentioned in a letter about the door. the Newmont Azurite in the same issue. Mindat.org Page Sponsorship Coming In November Donated books were given quite freely, if a purchase was made. Thanks to Diane Beckman for coming over on Saturday and spending MANY hours setting up the event. Special Event: Benefit Mineral & Gem Sale “Generous Donations by Blackman, Horowitz, Joseph, Walter & Others” The Mindat.org website is perhaps the most important mineral informational tool that most of us access every day in the United States. It is a non-profit entity. In order to keep it running and available, the NYMC has decided to sponsor the kunzite page on the site. Have an idea for a story? Write for the Bulletin of the NYMC. You’ll be glad you did! Mineral News More than 30 NYMC members found their The Mineral Collector’s way to Mitch’s apartment on a hot, humid, Newsletter Sunday to make purchases from the many A monthly publication filled with recent donations of minerals, books, descriptive articles, historical tidbits, supplies, jewelry and lapidary rough. new mineral finds and more! All in full color! The highlight for all were splendid specimens of quartz collected by Michael Subscriptions are just $30 per year Walter many years ago in Ellenville, NY. (12 issues) in the USA. Checks and Everyone was encouraged to select several major credit cards accepted. Order pieces and not miss this once-in-a-lifetime from: opportunity to add something special to Mineral News their mineral collections. 1885 Seminole Trail—Suite 202 Charlottesville, VA 22901-1160 100% of the monies from these purchases www.mineralnews.com will benefit the Club and especially help to [email protected] make this year’s Carnelian Banquet in October a memorable event and a little cheaper for us all! September 2018 Bulletin of the New York Mineralogical Club, Inc. 3 The World of Minerals The World of Minerals is a monthly column written by Dr. Vivien Gornitz on timely and interesting topics related to geology, gemology, mineralogy, mineral history, etc. Vivien is on a summer break – She’ll be back next month! We Finally Know Where Extremely Rare Blue The vast majority of Earth’s diamonds were forged Diamonds Come From somewhere in the mantle. Most diamonds formed between 1 and By Robin Andrews 3 billion years ago, at depths of around 150 kilometers (93 miles) beneath the continental crust, or 200 kilometers (124 Diamonds aren’t always pristine. In fact, most of the time miles) beneath the oceanic crust. they contain inclusions – trapped chemical compounds they’ve It’s likely that carbon dioxide, a major component of picked up along the way – which can give them a welcome or magmatic bodies, is buried at extreme depth, where the high unwanted hue. Take blue diamonds, for example: although rare, temperature and very high pressures there compress it into a it’s well known that it’s the element boron that gives them their diamond. It seems that they can only form in a very narrow famous shade. sliver of the upper mantle. There’s no way we’d be able to mine diamonds at their formation depth, though, so how the hell do they get to the shallow crust where we can dig them out? That took the most bonkers form of volcanic process known to science: kimberlite eruptions. Kimberlites are essentially cone-shaped pipes, and they only seem to appear in ancient continental crust. Their magma source was once exceedingly hot, very runny, and full of dissolved gases. When the internal pressure got a bit too much for the surrounding crust, it rushed up through the crust. There was likely a froth of carbon dioxide at the front, which was so buoyant that it moved at speeds of 1,000 kilometers (621 miles) The Hope Diamond, a particularly storied example per hour until it reached the surface. These eruptions no longer happen. It’s thought that they As explained by a new Nature study, precisely where this could only take place many millions of years ago, when Earth’s boron comes from has been something of a mystery for some innards were far hotter. time now. Fortunately, after tinkering with the geochemistry of dozens of these blue diamonds, the Gemological Institute of America (GIA) has provided us with an answer. Boron is near-ubiquitous in the crust, both oceanic and continental. Clearly, this is getting sucked down deep below to depths where diamond-forming fluid accumulates, but it’s not been clear how it got there. Taking a closer look at the mineral inclusions in these diamonds – many of which hadn’t been seen before – using X-rays and lasers, the team matched them with mineral ancestors, geochemical precursors if you like, found in oceanic crust segments. Specifically, these were segments that trapped seawater and A kimberlite mine in Siberia dragged it into the mantle – the superheated, colossal, solid layer that hides beneath the crust. As these broken crustal giants It’s a good thing they did, though. Their deep-seated magma headed through this layer, the seawater-enriched rocks were often included “alien rocks” from the mantle, named xenoliths “cooked”, and boron-rich fluids were released. – and those xenoliths frequently contained those elusive The physical structure of these mineral inclusions also diamonds. The speed of the eruptions was key: if these eruptions betray just how deep these blue diamonds form: in the lowest were any slower, the diamonds would transform into other, more parts of the mantle, at depths of at least 660 kilometers (410 commonplace forms of carbon.
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