Mineralogical Society of America, Founded December 30, 1919

MSA 2018 Calendar

2018 Calendar: Tourmaline     2017 Calendar: Wulfenite     Previous Lithographie/MSA calendars     The 1998 MSA calendar

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2018 Calendar Front cover
2018 Calendar Back cover

2018 Calendar: Tourmaline, a 16-month calendar.

In the gem gravels of Sri Lanka (Ceylon) any colored pebble that could not be identified was referred to in the local Tamil and Sinhalese languages as turmali, the root of the English word tourmaline. And to this day, the term tourmaline denotes not a single mineral, but a group of more than 24, related, complex silicates. Schorl, the dark, opaque, iron-rich species, is the most common tourmaline found in nature, while most of the gem material on the market is elbaite, and more rarely liddacoatite.

Tourmaline group minerals commonly occur in igneous and metamorphic rocks. Lacking value as an ore, tourmaline is primarily mined as a gem material as well as for the mineral specimen market. The gem species tend to form along with an assemblage of other minerals including quartz, beryl, and topaz, in igneous rocks known as pegmatites, while calciumrich species such as dravite and uvite more commonly occur in metamorphic settings such as marbles.

Being relatively hard (7 on the Mohs scale), having no cleavage, and occurring in colors spanning the visible spectrum, transparent tourmaline is an excellent gem material. More so given that several colors are frequently seen in a single crystal. The frequently elongated (prismatic) crystals may be zoned around their c-axes, which create concentric rings when viewed in cross section. “Watermelon” tourmalines are zoned crystals that are pink in the middle with green outer “rinds.” Popular single color varieties include “indicolite” (blue) and “rubellite” (pink to red). In recent years, the term Paraíba has been used to designate an electric-blue elbaite from the state of Paraíba in Brazil and controversially, elbaite of similar color from other localities.

Stones may be faceted or cut en cabochon, with wonderful “cabs” being fashioned from rough containing thousands of microscopic, parallel tubes to create a cat’s eye effect. For generations, carvers have worked tourmaline into beautiful, colorful sculptures. The nineteenth century Chinese Empress Dowager Cixi is said to have had a penchant for the pink tourmaline found in southern California around the turn of the century, and much of the production from San Diego County’s incredible pegmatites was shipped to China for carving.

The famous pegmatites in Minas Gerais, Brazil, are probably the most prolific sources of gem tourmaline. More recently, pegmatites in Afghanistan and Pakistan have produced superb specimens of elbaite and schorl. Other localities worldwide include, Vietnam, China, Myanmar, Madagascar, Russia, Mozambique, Nigeria and Namibia.

Elbaite is named for the Italian Isle of Elba, the source of the first studied and formally described specimens. In the United States, the first documented gem tourmaline was found in the early nineteenth century in Maine. These were followed by discoveries in Connecticut. Interest in the more modest east coast pegmatites waned as California’s rose in prominence. More than a century after their heyday, when I was in high school, I discovered the beauty of tourmaline in the crystals and crumbs that I found while digging in Connecticut’s abandoned pegmatite quarries. Those discoveries sparked a life-long passion, one that I hope emanates from these images of some of the magnificent tourmalines I have had the privilege of photographing.

Photography and text by Jeff Scovil

The calendar is published by Lithographie, LLC in cooperation with The Mineralogical Society of America, Martin Zinn Expositions, Tucson Gem and Mineral Society, Fine Mineral Shows, Denver Area Gem & Mineral Show, and Rocky Mountain Gems & Minerals.

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MSA 2017 Calendar

Order Publications Online (25% discount for MSA, CMS and GS members, except shipping)

2017 Calendar Front cover
2017 Calendar Back cover

2017 Calendar: Wulfenite, a 16-month calendar.

The calendar is published by Lithographie, LLC in cooperation with The Mineralogical Society of America, Martin Zinn Expositions, Tucson Gem and Mineral Society, Fine Mineral Shows and the Greater Denver Area Gem & Mineral Council.

Wulfenite! The mineral of deserts, where weathering veins of dull and boring lead sulfide slowly suck thin traces of molybdenum out of groundwater in order to make one of nature's most beautiful minerals. The square to octagonal plates and blocky crystals come in a wide range of colors, from the most treasured bright red specimens to brilliant orange, yellow, gray, and even dark blue.

The desert regions of southern Arizona and adjacent areas of northern Mexico are home to most of the greatest occurrences. In Arizona there are the big ten: the Red Cloud, Rowley, Old Yuma, Hilltop, Glove, Total Wreck, Gleeson, 79, Tombstone, and Tiger mines, along with a host of lesser localities. Stories are still told of the day in 1938 when Ed Over broke into the world's most precious pocket of fat, brilliant red crystals in the Red Cloud Mine. Is it any wonder that plans are afoot to have wulfenite officially declared the Arizona State Mineral?

In Mexico there are more fine wulfenite localities; the most famous are the San Francisco, Los Lamentos, and Ojuela mines, as these three have yielded hundreds of thousands of wulfenite specimens over the years. Europe has excellent occurrences as well, including the Bleiberg, Austria area where wulfenite was first described by Franz Xavier von Wulfen in 1785, and the Mezica Mine in Slovenia, where intrepid collectors are still bringing out fine specimens today. But, aside from the Americas, the undisputed queen of all wulfenite localities is the famous Tsumeb Mine in Namibia, where distinctive specimens in a range of habits and colors are known, from bright yellow to cognac red-brown and colorless to gray; the very rare deep blue wulfenite from Tsumeb is colored by inclusions of ilsemannite, a molybdenum oxide.

Wulfenite occurs worldwide wherever the climate and primary minerals are conducive. Bright red crystals from Iran are small but particularly attractive, and the Jianshan mine in the equally arid Xinjiang Uygar region of northwestern China has become a modern classic locality for red to orange wulfenite. The desert areas of Morocco, as at the Dalles Mine near Mibladen, are well-known sources of orange to yellow wulfenite. And recently an old locality at M'Fouati in the Congo has been producing fine new specimens as well. These are happy days for the wulfenite collector.

The mineral most commonly associated with wulfenite seems to be botryoidal mimetite in shades from moss-green at the Ojuela Mine to yellow at the San Francisco Mine to brilliant red at the Rowley Mine. At Tsumeb, bright yellow wulfenite crystals have even been found with emerald-green dioptase-what a color combination! Thus wulfenite possesses all of the characteristics that make it a collector favorite: great color, transparency or translucency, good sized crystals, high luster, interesting crystal shapes, and attractive (often contrasting) associated species, from a widely scattered array of localities worldwide, in quantities that allow every collector to own a handsome example. The photos shown here give an inkling of the tremendous beauty that arises when lead meets molybdenum in the desert.


Previous Lithographie/MSA calendars


2016 Calendar Front cover 2016 Calendar Front cover 2016 Calendar Front cover 2015 Calendar Front cover 2014 Calendar Front cover 2013 Calendar Front cover 2012 Calendar Front cover



The 1998 MSA calendar


1998 Calendar Front cover 1998 Calendar Back cover





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