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Jasper. Jasper, an aggregate of microgranular quartz and/or cryptocrystalline chalcedony and other mineral phases, [ 1][ 2] is an opaque, [ 3] 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. Jasper breaks with a smooth surface and is used for ...
Conchoidal fracture. A conchoidal fracture is a break or fracture of a brittle material that does not follow any natural planes of separation. Mindat.org defines conchoidal fracture as follows: "a fracture with smooth, curved surfaces, typically slightly concave, showing concentric undulations resembling the lines of growth of a shell". [ 1]
Fracture (mineralogy) In the field of mineralogy, fracture is the texture and shape of a rock's surface formed when a mineral is fractured. Minerals often have a highly distinctive fracture, making it a principal feature used in their identification. Fracture differs from cleavage in that the latter involves clean splitting along the cleavage ...
References. [ 1][ 2] Carnelian (also spelled cornelian) [ 3] is a brownish-red mineral commonly used as a semiprecious stone. Similar to carnelian is sard, which is generally harder and darker; the difference is not rigidly defined, and the two names are often used interchangeably. Both carnelian and sard are varieties of the silica mineral ...
Heliotrope (mineral) The mineral aggregate heliotrope (from Ancient Greek ἥλιος (hḗlios) 'sun' and τρέπειν (trépein) 'to turn'), also called Indian bloodstone or ematille, is a cryptocrystalline mixture of quartz that occurs mostly as jasper ( opaque) or sometimes as chalcedony ( translucent ). The "classic" bloodstone is ...
Scaphoid fracture. A scaphoid fracture is a break of the scaphoid bone in the wrist. [ 1] Symptoms generally includes pain at the base of the thumb which is worse with use of the hand. [ 2] The anatomic snuffbox is generally tender and swelling may occur. [ 2]
A compression fracture is a collapse of a vertebra. It may be due to trauma or due to a weakening of the vertebra (compare with burst fracture ). This weakening is seen in patients with osteoporosis or osteogenesis imperfecta, lytic lesions from metastatic or primary tumors, [ 1] or infection. [ 2] In healthy patients, it is most often seen in ...
Distal radius fracture. A Colles fracture as seen on X-ray: It is a type of distal radius fracture. A distal radius fracture, also known as wrist fracture, is a break of the part of the radius bone which is close to the wrist. [ 1] Symptoms include pain, bruising, and rapid-onset swelling. [ 1] The ulna bone may also be broken.