topaz

Identified! [Woman with large topaz crystal from Brazil, Museum of Natural History, Smithsonian Institution, Washington, D.C.] (LOC)

from The Library of Congress

• 10 older comments, and then…
• Nalim Namot said:

  could it he an artificially built monocrystal of carbon, aka diamond? just a thought, as the lady holds a ring...

• swanq said:

  I had a similar thought. This could be in a museum (from the drawers behind), perhaps the Smithsonian.

• Art Siegel said:

  I think that if this photo is from the 40's, as indicated, it is early for an artificial diamond, particularly of this size. I agree that the held ring indicates it's a gem. The group of photos is Washington-centric, so the Smithsonian is a good guess. I don't think it has to be artificial, since there are natural gems of this size. For example, www.gia.edu/gia-news-research-smithsonian-gem-mineral-col...

• swanq said:

  Well, the National Museum of Natural History has some huge natural crystals -- not diamond, but topaz. See www.mnh.si.edu/earth/text/dynamicearth/6_0_0_GeoGallery/g... The one pictured here is not one of the same topazes, but the size looks comparable. Quartz is another possibility.

• B-59 said:

  It could be IMO the topaz displayed in hyperphysics.phy-astr.gsu.edu/hbase/minerals/topaz.html with the caption: "This topaz crystal was so large, its transfer to the Smithsonian made the newspaper! The 75 kg (153 lb) crystal was the first giant gem-quality topaz crystal found. It weighed in at 350,000 carats. It was discovered in the late 1930s in Brazil. Later discoveries in the same area turned up a crystal more than four times this size. It is from Ferros, Brazil and scales about 35x45 cm. " The same topaz is visible in the first video on www.gia.edu/gia-news-research-smithsonian-gem-mineral-col... (EARTH'S TREASURES) at 1:54.