Cochise College            Student Papers in Geology     
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Roger Weller, geology instructor                                         

wellerr@cochise.edu
Quartz Family Gemstones-by Audrey LaClair
                            
                              Aventurine


         Aventurine is a form of translucent chalcedony that ranges in colors from green, orange, brown, gray, yellow, blue, peach, red or purple.  Green is the most searched for and valuable, while purple is very rare.  Aventurine glistens or shimmers which is called aventurescence.  Mica produces a silvery or yellow sheen.  When there is red or gray sheen, it is from Goethite and Hematite.  When the stone has a green sheen to it, it is from Fuschite.
 


photo by R.Weller
 

          The name Aventurine comes from the Italian word “a ventura”, which means “by chance”.  This is because of the discovery of aventurine glass by chance in the 18th century. 

 

          Aventurine is usually used as gemstones, beads, and cabochons, and can be used for ornamental figures as well.  Be careful with aventurine though, because it will fade in the sun.

 

          Aventurine is found in India, Brazil, Austria, Russia, Japan, Tanzania, Chile, Spain, and USA.

 

          Aventurine is said to treat disorders of the heart, lungs, glands, and the muscular system.  Aventurine is known to symbolize hope.  It helps one to honor their decisions and to trust decisions, as well as many other qualities.

 

Physical Properties

Mineral Information: Tektosilicates quartz (silica group)

Chemical Composition: SiO2

Color: Green, gold-brown

Hardness: 7

Specific Gravity: 2.65

Refractive Index: 1.544-1.563

From (http://www.firemountaingems.com/beading_information/beading_resources.asp?docid=gmstnprprtsvntr&sact=search).

 

References:

http://www.pgrgem.com/color/datasheets/pgraventur.html

http://en.wikipedia.org/wiki/Aventurine

http://www.jewelrymall.com/stones/aventurine.html

http://www.starphirejewelry.com/aventurine.html

http://www.destarte.com/aventurine.html

http://www.bernardine.com/gemstones/aventurine.htm

http://www.firemountaingems.com/beading_information/beading_resources.asp?docid=gmstnprprtsvntr&sact=search