Heliotrope (mineral) is Indonesia, especially in Purbalingga district. It is also found in Armenia, Azerbaijan, Brazil, Bulgaria, China, Australia, and the United States. There is also an outcrop of bloodstone on the Isle of Rum, in Scotland. 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
Aluminium alloy inclusions where carbon anodes and cathodes are in contact with the mix. Later in the process, any carbon tools in contact with the liquid aluminium can react and create carbides. In aluminium alloys containing magnesium, magnesium oxides (MgO), cuboids (MgAlO-cuboid) and metallurgical spinel (MgAl2O4-spinel) can form. They result from the reaction between magnesium and oxygen in the melt. More of them will form with time and temperature. Spinel can be highly detrimental because of its big size and high hardness. Particles of refractory material in contact with aluminium can detach and become inclusions. We can find graphite inclusions (C), alumina inclusions