Snowflake obsidian occurs as the glass devitrifies, when tiny clusters of needle-like crystals called spherulites begin to form.

Snowflake obsidian occurs when obsidian begins to devitrify, and its constituents start to crystallise out of the amorphous mineral. It is black and white, and in two states of being, so symbolises the Chinese concept of Yin and Yang. For this reason it can be used as a general balancer.  Yin and Yang does not just denote a meeting of opposites.  There must always be a flow from one to the other, as stagnation is unhealthy. Snowflake obsidian exemplifies this flow, as it changes from one state to another, and also represents the crystallisation of our true selves out of the potential we are born with. Physically, the sense of flow can be applied to circulatory problems.