Cameo glass

Goldstein, S. M., L. S. Rakow, and J. K. Rakow (1982), Cameo Glass Masterpieces from 2000 Years of Glassmaking, The Corning Museum of Glass, Coming, NY. 

Mommsen, H., A. Brining, H. Dittmann, A. Hein, A. Rosenberg, and G. Sarrazin (1997a), Early Roman cameo glass X ray fluorescence analysis induced by synchrotron radiation (S.I.X.R.E), Glass Sci. Technol. (Glasstechnische Berichte) (July), 211-219. 

CAM plants Abbreviation for crassulacean acid metabolism plants. cambium The layer of cells between the phloem and the wood of a tree, cameo A small relief carving on a different colored background, made from either onyx or two-color layered glass. 

Fracture Fracture describes the way a substance breaks when it neither cleaves nor parts (breaks along plane of weakness). The most common kind of visible fracture is conchoidal, which produces curved, smooth surfaces (glass, quartz). Freshwater pearl one that occurs in a freshwater (non-marine) mollusk. Gem a general term used to describe precious and semi-precious stones, usually after they have been cut and polished. In archaeology, it refers only to engraved stones (cameo, intaglio, seals, etc.). 

Cameo. (1) Glass jewellery, etc., made of two or more layers of glasses of different colours and carved in relief. 

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