Gemmes & Gemmologie

Rare Opalescent Gem Ammonite, Cretaceous, ca. 75000000 BCE, Alberta, Canada, 16 1/2 × 14 1/2 in, 41.9 × 36.8 cm © ArtAncient Ammonites take their name from their spiral shells which reminded  the ancients of Ammon's curled horns. Found throughout the world, those from the Bearpaw Formation are regarded as the most beautiful. Contact Gallery for price.

Lot 2219. Large Conch Pearl, Strombus gigas or "Queen Conch", Caribbean Sea; weighing approximately 20.77 carats and measuring 16.98 x 14.02 x 11.55mm. Sold for US$ 18,750 (€15,818) inc. premium. Photo: Bonhams. This conch pearl is of particularly large size for the species. Of "baby" pink hue and of slightly baroque form, having an excellent flame pattern iridescent, with excellent luster. Bonhams. LAPIDARY WORKS OF ART, GEMSTONES AND MINERALS, 6 Dec 2017, 10:00 PST - LOS ANGELES

Lot 2218. Unusual Large White Conch Pearl, Strombus gigas or "Queen Conch", Caribbean Sea; weighing approximately 16.93 carats and measuring 14.64 x 12.39 mm. Sold for US$ 7,500 (€6,327) inc. premium. Photo: Bonhams. A large non-nacreous pearl having a plump oval shape, a virgin white body color and excellent, minute-grained flame pattern iridescence. Bonhams. LAPIDARY WORKS OF ART, GEMSTONES AND MINERALS, 6 Dec 2017, 10:00 PST - LOS ANGELES

Lot 2217. Fine Conch Pearl, Strombus gigas or "Queen Conch", Caribbean Sea; weighing approximately 5.60 carats and measuring 12.23 x 8.71 x 6.95mm mm. Sold for US$ 5,000 (€4,218) inc. premium. Photo: Bonhams. Of classic oval shape having excellent flame pattern iridescence, beautiful porcellanous luster and a pastel baby pink hue. This pearl would make a fine pair with lot 2216. Bonhams. LAPIDARY WORKS OF ART, GEMSTONES AND MINERALS, 6 Dec 2017, 10:00 PST - LOS ANGELES

Lot 2216. Deep Rose Conch Pearl, Strombus gigas or "Queen Conch", Caribbean Sea; weighing approximately 5.69 carats and measuring 12.32 x 8.67 x 6.90mm. Sold for US$ 10,000 (€8,436) inc. premium. Photo: Bonhams. Of ovoid form, distinguished by its perfect of shape and color--a rich, well-saturated deep rose which exhibits a beautiful flame pattern iridescence. Bonhams. LAPIDARY WORKS OF ART, GEMSTONES AND MINERALS, 6 Dec 2017, 10:00 PST - LOS ANGELES

Lot 2299. "A Member of the 100 Carats Club". Exceptional Arizona Amethyst, Four Peaks, Arizona; weighing approximately 118.0 carats and measuring 40.67 x 23.95 x 18.92mm. Sold for US$ 27,500 (€23,200) inc. premium. Photo: Bonhams. In fact, the Arizona Four Peaks Amethyst mine is believed to be the only precious stone mine in the United States that requires a helicopter to transport supplies in and take mined material out. Located in the most rugged parts of the Matzanal Mountains, forty-six miles from Phoenix, the miners... [Lire la suite]

Lot 2023. The Official State Gemstone of California. Benitoite, Benitoite Gem Mine, San Benito County, California; weighing approximately 2.08 carats and measuring 8.18 x 6.76 x 4.94mm. Sold for US$ 35,000 (€29,528) inc. premium. Photo: Bonhams. Around the turn of the 19th Century, a prospector discovered a blue material that he believed to be sapphire. Examination by experts determined the new gem material to be an unknown mineral. In addition, it turned out that the new material represented a previously unknown... [Lire la suite]

Lot 2458. Nigerian "Paraiba-type" Tourmaline, weighing approximately 50.6 carats and measuring 26.03 x 19.85 x 15.71mm. Sold for US$ 35,000 (€29,528) inc. premium. Photo: Bonhams. This is a large stone for the species and an exemplary one at that. Faceted as a pear-shape, a cut which beautifully displays the very high clarity of the stone. The color is an attractive blue. Accompanied by a Gemological Institute of America report number 16940742 dated March 28, 2008 stating that the tourmaline contains copper and manganese... [Lire la suite]

Lot 2466. Large and Impressive Rubellite Tourmaline, Nigeria, weighing approximately 85.27 carats and measuring 27.59 x 20.43 x 15.86mm mm. Sold for US$ 37,500 (€31,637) inc. premium. Photo: Bonhams. Faceted as a cut-cornered emerald-cut with scissors-cut crown facets, this is a world class tourmaline by any measure. Notable for its large size, which still allows it to be mounted as a ring or pendant and its exceptional clarity and deep, pinkish red color. This is a stone worthy of attention by the most serious collector.... [Lire la suite]

Selenite, Robert R. Wiener Collection. Photo by Paul Mutino. GREENWICH, CONN.- Visitors to the Bruce Museum can take a global tour of the splendor, wonder, and science of minerals as Treasures of the Earth: Mineral Masterpieces from the Robert R. Wiener Collection opens to the public. Continuing through April 1, 2018, this exhibition offers a rare chance to discover the wondrous beauty and amazing properties of world-class minerals from a remarkable private collection. Approximately 100 dazzling specimens are on... [Lire la suite]