What is Obsidian?

Obsidian is a kind of black material like glass formed when lava cools in a short time Because of the fast cooling rate, the crystal formed in the material is very few This makes Obsidian essentially a natural glass and useful due to the lack of crystals In particular, it can be cut into sharp edges It is a very popular weapon material in the stone age, and it is still used in some surgical instruments It is not difficult to identify obsidian It's often black and shiny even when it's not polished It is composed of more than 70% silica, which is also the cause of its color However, if obsidian is mixed with some minerals, it will follow other colors For example, a high iron or magnesium content can cause the rock to appear dark green rather than black Some Obsidian are derived from snow flakes of cristobalite at the top In other cases, the substance bubbles and forms a layer This can produce a rainbow or golden obsidian However, the two variants are rare and hard to find Obsidian is not a real mineral or rock because it does not contain crystal structure Some people call it quasi mineral Quasi mineral is a mineral like substance lacking crystal structure Other quasi minerals include Opal and pearls Obsidian is a relatively soft material with a Mohs hardness of only 5-5.5 However, despite its softness, it is the preferred material for weapons because it can be refined into very sharp edges In North America and other regions, arrows made of obsidian can still be found It can also be used for decorative purposes, such as the stone statue on Easter Island Some surgeons, especially cardiac surgeons, use scalpels and scalpels made of obsidian This kind of knife is very sharp and causes little damage to the tissue during cutting Because of the high sharpness, these special surgical cutting equipment can often reduce the recovery time Obsidian can be found in many parts of the earth, especially in quarries or where volcanoes are active However, it will deteriorate into small glass crystals over time.