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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 ornamentation or as ...
Breccia is composed of coarse rock fragments held together by cement or a fine-grained matrix. [5] Like conglomerate, breccia contains at least 30 percent of gravel-sized particles (particles over 2mm in size), but it is distinguished from conglomerate because the rock fragments have sharp edges that have not been worn down. [6]
Orbicular jasper from Madagascar. Orbicular jasper is a variety of jasper which contains variably-colored orbs or spherical inclusions or zones. In highly silicified rhyolite or tuff, quartz and feldspar crystallize in radial aggregates of needle-like crystals which provide the basis or seed for the orbicular structure seen in this kind of jasper. [1]
A rough specimen of bloodstone. Heliotropes (from Ancient Greek ἥλιος (hḗlios) 'sun' and τρέπειν (trépein) 'to turn') (also called ematille, Indian bloodstones, or simply bloodstones) are aggregate minerals, and cryptocrystalline mixture of quartz that occurs mostly as jasper or sometimes as chalcedony (translucent).
Biggs jasper was first found around 1960 at the bottom of a creek near Biggs Junction, Oregon, after possibly being carried some distance by water from the outcrop where it originated. More of the stone was found in the 1960s, particularly during road works in 1966 when U.S. Route 97 was relocated through a canyon south of Biggs Junction.
The locations of National Register properties and districts (at least for all showing latitude and longitude coordinates below), may be seen in an online map by clicking on "Map of all coordinates". [1] This National Park Service list is complete through NPS recent listings posted January 24, 2025. [2]
This is intended to be a complete list of the properties on the National Register of Historic Places in Jasper County, South Carolina, United States. The locations of National Register properties, for which the latitude and longitude coordinates are included below, may be seen in a map.
Incomplete alteration causes the physical properties of serpentines to vary widely. Antigorite is the polymorph of serpentine that most commonly forms during metamorphism of wet ultramafic rocks and is stable at the highest temperatures—to over 600 °C (1,100 °F) at depths of 60 km (37 mi) or so. In contrast, lizardite and chrysotile ...