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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]
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 ...
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]
This is a list of properties and districts in Ohio that are listed on the National Register of Historic Places. There are over 4,000 in total. Of these, 73 are National Historic Landmarks. There are listings in each of Ohio's 88 counties.
In 2004, the company sold 25 properties for $103.1 million. [5] [6] In 2007, the company sold University Mall in Tampa, Florida for $149 million. [7] In 2010, the company closed a $320 million joint venture with The Blackstone Group, which included the sale of a 60% interest in 2 malls. [8]
Verd antique is very similar in colour to the national gemstone of Ireland, Connemara marble.Connemara marble differs from the verd antiques in that it is an actual marble, rather than a serpentinite breccia, despite also having a very high serpentine content.
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).
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 ...