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Mystic Larvikkite

A dark, shimmering gemstone, sometimes called black Labradorite. As beautyful as they come. Avaiable in two sizes, one suitable for rings and one for pendants - or...

 

Size: 18x13x5,7-6 mm and 26x18x7-8 mm

 

In stock:  aprox 10 of each size

 

Price:  USD 5.00/smaller, 6.70/larger

Select size

Larvikite is a variety of monzonite*, notable for the presence of handsome, thumbnail-sized crystals of feldspar. These feldspars are known as ternary because they contain significant components of all three end-member feldspars. The feldspar has partly unmixed on the micro-scale to form a perthite, and the presence of the alternating alkali feldspar and plagioclase layers give its characteristic silver blue sheen (Schiller effect, labradorescence) on polished surfaces. Olivine can be present along with apatite, and locally quartz. Larvikite is usually rich on titanium, with titanaugite and/or titanomagnetite present. The name originates from the town of Larvik in Norway, where this type of igneous rock is found. Many quarries exploit larvikite in the vicinity of Larvik. Sometimes Larvikite is referred to as black Labradorite.

 

* Monzonite is an igneous intrusive rock. It is composed of approximately equal amounts of plagioclase and alkali feldspar, with less than 5% quartz by weight.[1] It may contain minor amounts of hornblende, biotite and other minerals. If quartz constitutes greater than 5%, the rock is termed a quartz monzonite.


 

 

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Latest update: 22 september 2015