Obsidian is the name given to volcanic glass – a rock rather than a mineral, it is a mixture of cryptocrystalline grains of silica minerals in a glass-like suspension and displays a conchoidal fracture. Obsidian forms during the last stage of volcanic activity, close to the earths surface cooling occurs too quickly for crystals to grow. Natural obsidian varieties include black, bluish, mahogany, gold & silver sheen, rainbow, etc. – the colors due largely to refraction by microscopic bubbles (and microscopic mineral inclusions such as magnetit in “Rainbow Obsidian”). Lustre: Vitreous
The Merkabah is a two pyramids inverted into each other. Based on sacred geometry it has been used by many cultures, although today it is most commonly associated with the Hebrew culture and is called the Star of David. Within the kabbalah (spiritual Jewish tradition) it is seen as an actual vehicle made of light that carries us towards enlightenment; the practice of picturing yourself standing with in this shape is said to train the mind and open our awareness and spiritual evolution.