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Amber and plastic reactions to illumination.
Plastic Amber Imitation in a Rosary

Examination reveals both amber and Bakelite plastic beads in a rosary submitted for identification.

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Natural-color yellow sapphires with FTIR features of Punsiri-treated sapphire
“Punsiri”-type FTIR Spectral Features in Natural Yellow Sapphires

Testing of natural-colour yellow sapphires from Australia and Thailand with the FTIR features of “Punsiri” heat-treated material.

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Purple pyrope-almandine garnets from Manica Province, Mozambique
Purple Pyrope-Almandine Garnet From Mozambique

Analysis of attractive purple garnets from a new deposit in central Mozambique.

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Musgravite from Myanmar
Musgravite from Myanmar

Two small, near-colourless stones reportedly from Myanmar (0.11 and 0.24 ct; figure 1) were recently loaned to GIA for examination for identification.

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Blue cat's-eye apatite
Blue cat's-eye apatite

Deep blue apatite with a cat’s-eye effect, however, is very rare.

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Demantoid garnet fossil pseudomorphs

In these two extremely rare specimens, demantoid garnet has replaced coral and gastropod fossils.

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Faceted wurtzite from Tanzania

The rarity and value of faceted wurtzites from Tanzania are sure to draw the attention of gem collectors.

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Bangle of polymer-impregnated aventurine quartz
Polymer-Impregnated Aventurine Quartz, a New Imitation of “Ice Jade”

A bangle, thought to be jadeite jade, is revealed by laboratory testing to be polymer-impregnated aventurine quartz.

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Fire Opal
Coated Fire Opal in the Chinese Market

An investigation of a coated fire opal recently found in the Chinese market.

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Bright yellow diamonds from Sierra Leone

Examination of strongly yellow diamonds from the Zimmi area of Sierra Leone revealed graphitised feather inclusions.

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