June 27, 2013

Mosaic Jasper


                                                       



As someone who has always been interested in gemstones and jewellery I recently came across Mosaic Jasper.


It is most definitely not a precious stone and thus is easily affordable, depending on the setting.


Jasper is a well-known and inexpensive stone.


According to this site:
Jasper is derived from the Greek for "spotted stone". Jasper is usually considered a chalcedony, but put by scientists in a group by itself because of its grainy structure. The finely grained, dense jasper contains up to twenty percent foreign materials that determine its color, streak and appearance. Uniform jasper is rare. It usually is multicolored, striped spotted or flamed.

Some of the most treasured gems are those that show a picture that appears to be taken from nature, called "landscapes". Oregon's Biggs Jasper is now the most common source. Another specialty is bloodstone or blood jasper, also known as "heliotrope", a dark green
chalcedony or jasper with flecks of red. Bloodstone is the Zodiac birthstone for Aries.
Jasper comes in all colors, mostly striped, spotted or flamed. A variety of trade names specify colors, appearance or composition.

Agate jasper: Yellow, brown or green blended, grown together with agate
Egyptian jasper: Strongly yellow and red
Banded jasper: Layered structure with more or less wide bands
Basanite: Fine-grained black
Blood jasper: Bloodstone, dark green with flecks of red
Hornstone: Very fine grained, gray, brown-red, more rarely green or black
Scenic jasper: Brown marking caused by iron oxide, resembling a landscape. Oregon's "Biggs Jasper" is now the most common source. "Bruneau Jasper", from Bruneau Canyon, Idaho, is praised for its blue "skies".
Moukaite: Pink to light red, cloudy
Plasma: Dark green, sometimes with white or yellow spots
Silex: Yellow and brown-red spotted or striped
Chemical composition: SiO2 silicon dioxide


Finding information about Mosaic Jasper has been difficult, and it seems it is sometimes known as Rainbow Calsilica.


I still can’t seem to ascertain if it is a genuine gemstone or if it is man-made although some sites say it comes from China. The pieces I have are from Hong Kong.


However it certainly makes very attractive pieces of jewellery and when I wear my pieces I get  lots of comments and compliments for it because it is so colourful and unusual!


I am quite happy to wear it no matter if it is man-made or not.
Maybe one day I will find out for sure!


Most of the pictures here are from the internet and resemble some of the pieces I have have purchased.       

Update: I have now seen so many pictures of so many different kinds of Mosaic Jasper that I am finding it harder to believe it is a manufactured gem.  




A polarised light micrograph of a sample of volcanic 'ocean jasper' found only in Madagascar. Picture: Bernardo Cesare: Daily Telegraph