Jasper Jasper Jasper, an aggregate of microgranular quartz and/or chalcedony and other mineral phases, is an opaque, impure variety of silica, usually red, yellow, brown or green in color; and rarely blue. The common red color is due to iron(III) inclusions. The mineral aggregate breaks with a smooth surface and is used for ornamentation or as a gemstone. It can be highly polished and is used for items such as vases, seals, and snuff boxes. The specific gravity of jasper is typically 2.5 to 2.9. A green variety with red spots, known as heliotrope (bloodstone), is one of the traditional birthstones
Non-metallic inclusions allows the elimination of most natural and foreign inclusions from the metal. However its general content in different steels can vary between wide limits and has a big influence on the metal properties. Non-metallic inclusions, the presence of which defines purity of steel, are classified by chemical and mineralogical content, by stability and by origin. By chemical content non-metallic inclusions are divided into the following groups: The majority of inclusions in metals are oxides and sulfides since the content of phosphorus is very small. Silicates are very detrimental to steels, especially if it has to undergo heat treatment at a