Heliotrope (mineral) Heliotrope (mineral) The mineral aggregate heliotrope (from Greek ἥλιος, "hḗlios" “Sun”, τρέπειν, "trépein" “to turn”), also known as bloodstone, is a variety of jasper or chalcedony (which is a cryptocrystalline mixture of quartz). The "classic" bloodstone is green jasper (chalcedony) with red inclusions of hematite. The red inclusions are supposed to resemble spots of blood, hence the name "bloodstone". The name "heliotrope" derives from various ancient notions about the manner in which the mineral reflects light. These are described, e.g., by Pliny the Elder ("Nat. Hist." 37.165). Heliotrope was called "stone of Babylon" by Albert the Great and he referred
Aluminium alloy inclusions is a fracture test method. Liquid metal is cast into a mold containing notches. Once solidified, the resulting bar is bent to expose a fracture surface. The visual observation of inclusions on the fracture is used to determine a K-value for the melt and compared to a preset standard. This method is rather imprecise and therefore only suitable when metal contents large inclusions and inclusion clusters. The LiMCA method measures the total concentration and size distribution of inclusions present in aluminum alloys. Its measuring principle is based on an objective and user-independent method. The LiMCA CM system can characterize the