MINERAL OF THE MONTH
May 2008: Apophylite
The mineral of the month for May 2008 is Apophylite. This specimen was acquired from a Brazilian dealer who was liquefying his entire inventory at the Tucson show a couple of years ago. He said something about wanting to go fishing. Apophyllite is in the Silicate class of minerals, which tend to be translucent and are lower in specific gravity and harder than most minerals. All silicates contain the silicate atomic structure, whose fundamental building block is the tetrahedron, in which one silicon atom is surrounded by four equally spaced oxygen atoms. Other silicates include quartz, chalcedony, opal, orthoclase feldspar, and amazonite.
Apophyllite is a hydrous calcium potassium fluorsilicate. It can either be colorless or white, gray, green, yellow, or red. It has a hardness of 4 ½ to 5, a specific gravity of 2.3, and has perfect cleavage in one direction. The crystals are tetragonal, usually cube like or tabular and square in cross section. It forms at low temperatures and is commonly found in cavities in basaltic pockets, where it is often associated with zeolites and prehnite. Although this specimen is from Brazil, Apophyllite can be found in the copper mines on the Keweenaw Peninsula among other places world-wide.
The name, Apophyllite, means "to leaf apart" in Greek. The name derived from the tendency of the crystals to peel off when specimens are heated due to the sudden loss of water molecules within the structure. Although collectors refer to this mineral is Apophyllite, it is no longer officially classified as a mineral. Originally, the group name referred to a specific mineral, but was redefined in 1978 to stand for a class of minerals of similar chemical makeup. Apophyllites are popular as with collectors due to their well-defined crystals, color, and abundance.
The metaphysical properties of Apophyllite are thought to enhance your analytical skills and enable you to act in a truthful and honest manner. It can also be used to help you evaluate your behaviors and attitudes so that you can identify and correct any shortcomings.
Mineral of the Month Archives
May 2007: Rainbow Fluorite
June 2007: Lake Superior Michipicoten Agate
July 2007: Labadorite
August 2007: Rain Flower Agate
Fall 2007: Malachite
December 2007: Nepheline Syenite
January 2008: Native Copper
February 2008: Amazonite
March 2008: Lake Superior Agate
April 2008: Shadow Agate
May 2008: Apohpylite
June 2008: Ocean Jasper
Summer 2008: Marra Mamba Tiger's Eye
September 2008: Mohawkite
October 2008: Mexican opal
November 2008: Prehnite
December 2008: Picture Jasper
January 2009: Sea Shell Jasper
February 2009: Polychrome Jasper
March 2009: Selenite Desert Rose
Spring 2009: Coyamito Agate
July 2009: Obsidian Needles
August 2009: Goethite
September 2009: Banded Iron Formation
Fall 2009: Fairburn Agate
March 2010: Fossilized Dinosaur Bone
April/May: 2010 Kentucky Agate
June 2010: Nantan Meteorite
July 2010: Mookaite Jasper
Aug/Sept 2010: Polyhedroid Agate
Fall 2010: Ammonite Fossil
September 2011: Petoskey Stones
Spring 2011: Petrfied Wood
Winter 2011: Argentina Condor Agate
January 2012: Mary Ellen Jasper
March 2012: Mexican Crazy Lace Agate
June 2012: Moqui Marbles
September 2012: Chlorastrolite Greenstone
March 2013: Jacobsville Sandstone
August 2013: Unakite
November 2013: Skip-an-Atom Agate
April 2014: Tiger's Eye
September 2014: Black Corundum
February 2015: Condor Agate
June 2015: Petoskey Stone
November 2015: Slag
June 2016: Lake Superior Copper Replacement Agates
March 2017: Chert
July 2017: Kona Dolomite
December 2017: Septarian Nodule
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Gitche Gumee Museum.
E21739 Brazel Street
Grand Marais, Michigan 49839