Obsidian Rocks

An obsidian rock is a type of extrusive igneous rock, formed after rapid solidification of lava that is rich in silicate minerals. Chemically, it comprises silicon dioxide as one of the primary constituents, with several other impurities. According to chemical composition, the color and texture of an obsidian rock differ with one another. For example, presence of magnesium and iron imparts a blackish to greenish specks in the obsidian rocks. With this brief introduction, let's take a look at obsidian rocks and some interesting facts about these glassy textured stones.

Obsidian Rock Facts

Archaeological studies found evidences regarding usage of obsidian rocks as weapons and cutting tools in ancient times. For a layman, obsidian rock resembles a smoky quartz in color and appearance. However, there are some key points that characterize each of these types of igneous rock. A notable difference is alteration or absence of crystal properties in obsidian, which are prominent in quartz. Also, the color distribution in these rocks is more even than smoky quartz. Read the following information to know more about obsidian rocks.

Properties
Obsidian rock texture resembles glass. Classified under amorphous rocks, its hardness is much lesser than quartz. In comparison to igneous rocks like pumice, obsidian rocks are devoid of large voids. Identifying attributes of obsidian rocks are lack of crystal faces, distinctive flow bubbles, conchoidal fracture upon breakage and presence of other igneous rocks.

Formation
The phenomenon behind the formation of obsidian rock is very interesting. As silicate rich lava extrudes from inside the earth's crust, it falls over water bodies or other cool surfaces. And the result is the immediate formation of obsidian rocks, without having time for crystallization. This is the main reason why, obsidian rocks are amorphous and do not have any crystal system.

Types
These rocks are divided into many types, based on several attributes, out of which flow bubble is one. The air bubbles imparted in course of magma flow are aligned in a regular pattern, giving specific effects. Sheen obsidian has golden effects; while rainbow obsidian possesses characteristic rainbow luster. Another common black type is snowflake obsidian, having inclusions of small whitish crystals.

Uses
Obsidian rocks, due to their attractive glass like texture, is used as semiprecious stones. Also, it is kept as decorative specimens, especially after designs are carved over the surface. They are also used in the manufacture of surgical blades. Unlike steel and metallic blades, the cutting edge of an obsidian blade is even throughout the length, thus giving smooth cuts.

Crystal Healing
In recent times, this igneous rock has become popular in crystal healing. They help promote the physical well-being, digestive health and circulation system of an individual. As per crystal therapists, obsidian rocks serve as protective stones, thereby absorbing negative energies and transforming them. It should be employed only under the guidance of a crystal expert.

A pure obsidian rock is translucent and dark in color. The texture and chemistry of these rocks define them as mineraloids, but not actually a mineral. Speaking about their occurrence, they are found in parts of United states, Canada, Mexico, Argentina, Italy, Kenya, Greece and Iceland. If you are interested in owning this glassy igneous rock, look out for museums that offer obsidian rocks for sale.