Most of these fabulous specimen
tourmalines had been dislodged from their quartz matrix and had fallen into soft clay, which cushioned them from any damage.
Manning, "An optical absorption study of the origin of colour and pleochroism in pink and brown
tourmalines," The Canadian Mineralogist, vol.
A major piece in the collection, Hanan, named after the Goddess of the Morning, is a jeweled garland of wild berries filled with lustrous golden and white pearls, whose vines are populated with tiny
tourmaline insects.
Eight years (and many
tourmalines) later, an elusive multi-RI stone was found.
The volume then discusses nine different classes of
tourmalines, providing one or more striking color photographs on each page and also includes chapters discussing blue chalcedony, fire agate, and matrix opal.
Michael Scott's gem collection is the only one in the world with enough blue-green, copper-bearing elbaite
tourmaline, known in the gem trade as Paraiba
tourmaline, to fill an entire display case.
Prasad, "Study of structural disorder in natural
tourmalines by infrared spectroscopy," Gondwana Research, vol.
"Paraiba"
tourmalines from Brazil and Africa--Origin determination based on LA-ICP-MS analysis of trace elements.
A few small, pink or dark green or a darkish purple
tourmalines appeared, and I bought some of them after hard negotiations; as I had found on the previous trip, there were no bargains to be found on this mineral species.
Martin (representing Maria Sokolov and Jeffrey Patterson) presented a paper on "The unusual 'noble' amazonitic orthoclase in the Minh Tien 'hybrid' granitic pegmatite, Luc Yen district, Vietnam." They reported analyses revealing a significant lead level in some
tourmalines. Their abstract, which contains interesting genetic information as well, is as follows:
John Bradshaw, Coast-to-Coast Rare Stones International, Nashua, New Hampshire, USA, for 21 bags containing part-cut crystals of: apatite (Canada and Mexico), cassiterite (Namibia), celestine (Kansas, USA), cerrusite (Namibia), crocoite (Tasmania, Australia), diaspore (Turkey), oligoclase (Kenya), pollucite (Conneticut, USA), scheelite (Pakistan and Arizona, USA), smithsonite (Namibia), sphalerite (Spain),
tourmaline (Maine, USA, and Afghanistan), tugtupite (Greenland), willemite/leucophoenicite (New Jersey, USA) and zincite on calcite (New Jersey); and also for 95 faceted mixed-shape
tourmalines, mostly pink, green and blue.
As you enter the mineral section of Grieger's, your eyes will be attracted to a massive display of Santa Rosa and Cruziero mine
tourmalines ...
* 'The Structure of
Tourmalines' briefly reviews the crystal structure of the mineral to help put the geometric patterns seen in slices into context.
In the huts above ground we saw a few multicolored
tourmalines, the largest measuring 10 cm; the crystals were not terminated, but their colors were wonderful.
Fine
tourmalines were also displayed in the collection from the Sorbonne, and the University of California at Santa Barbara had another very informative educational display, "Chemistry, Crystallography and Origin of
Tourmaline."
