![]() ![]() Except for silica, most also contain some admixtures such as iron oxides/hydroxides, feldspars, and epidotes (Żaba, 2010). In general, all jasper types have specific physical, chemical, and aesthetic properties that make them a valuable material for jewelry. Examples include, respectively, radiolarites such as mookaite jasper (Campos-Venuti, 2012), quartzites such as Sioux Falls jasper (Dietrich, 2009), and rhyolites such as orbicular jasper and picture jasper (Żaba, 2010 Polk, 2012). Hence, the jasper group is characterized by sedimentary, metamorphic, or igneous rocks. Götze (2010) defined it as a mixture of microcrystalline silica with iron oxide and illite, while Kievlenko (1980) classified it as a metamorphic or metasomatic material. Manutchehr-Danai (2010) considered jasper a dense, translucent to opaque impure variety of chalcedony or chert. In addition, the nomenclature and classification of jaspers are not well coordinated in gemology and petrology (Kostov, 2010). Unfortunately, the term “jasper” has become commercialized and misused by many sellers. Jasper (from the ancient Greek for “spotted stone”) has a variety of colors, patterns, and textures that make it a very popular gemstone worn in jewelry and sought after by collectors and geologists. The authors recommend the use of the term “dalmatian stone” rather than “dalmatian jasper,” since the material does not meet the gemological definition of jasper. Black spots found in the examined rock’s mass were recognized as arfvedsonite. It consists predominantly of feldspars (mesoperthite), quartz, alkali amphiboles, and lesser amounts of hematite and epidote. Our research revealed that this gemstone is a peralkaline rock of uncertain provenance. “Dalmatian jasper,” also known as “dalmatian stone,” is a popular decorative gemstone with a unique appearance resembling the spotted coloration of the Dalmatian dog breed. Right: A polished bracelet (1 cm bead diameter) alongside a pendant measuring 3 cm in length. ![]() Left: A rough block-shaped specimen measuring 1.5 × 1.5 × 1 cm. Dalmatian stone samples examined in this study reveal a spotted appearance connected with the presence of alkali amphiboles disseminated through feldspar-quartz matrices. Comprehensive CAD/CAM For Jewelry Certificateįigure 1. ![]()
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