|Serpentine var. Ribbonstone
|The serpentine group describes a group of common rock-forming hydrous magnesium iron phyllosilicate
minerals; they may contain minor amounts of other elements including chromium, manganese, cobalt or nickel. In
mineralogy and gemology, serpentine may refer to any of 20 varieties belonging to the serpentine group. Owing
to admixture, these varieties are not always easy to individualize, and distinctions are not usually made. There
are three important mineral polymorphs of serpentine: antigorite, chrysotile and lizardite.
The serpentine group of minerals are polymorphous, meaning that they have the same chemical formula, but the
atoms are arranged into different structures, or crystal lattices. Chrysotile, which has a fibrous habit, is one
polymorph of serpentine and is one of the more important asbestos minerals. Other polymorphs in the serpentine
group may have a platy habit. Antigorite and lizardite are the polymorphs with platy habit.
Many types of serpentine have been used for jewelry and hardstone carving, sometimes under the name false
jade or Teton jade.
Most serpentines are opaque to translucent, light (specific gravity between 2.2–2.9), soft (hardness 2.5–4),
infusible and susceptible to acids. All are microcrystalline and massive in habit, never being found as single
crystals. Lustre may be vitreous, greasy or silky.
Colors range from white to grey, yellow to green, and brown to black, and are often splotchy or veined. Many are
intergrown with other minerals, such as calcite and dolomite. Occurrence is worldwide; New Caledonia, Canada
(Quebec), US (northern California, Rhode Island, Connecticut, Massachusetts, Maryland and southern
Pennsylvania, Afghanistan, Britain (the Lizard peninsula in Cornwall), Ireland, Greece (Thessaly), China, Russia
(Ural Mountains), France, Korea, Austria (Styria and Carinthia), India (Assam, and Manipur), Myanmar (Burma),
New Zealand, Australia, Norway and Italy are notable localities.
|Item # SERPRIB09171232
Serpentine var. Ribbonstone
|Here's an excellent polished face multi banded formation Serpentine var. Ribbonstone in zebra-like black and white
layers. The white bands take on a pearlescent appearance under sunlight when the piece is moved and viewed
from the correct angle (similar to the way labradorite shows color). This is a very unique specimen from Australia.
specimen weighs 6.46 oz or 0.4 lbs (183g) and measures 2.9 x 1.7 x 1.6 inches (7.3 x 4.4 x 4.1cm)