Fire Agate

Fire agate is a kind of chalcedony, itself a variety of quartz, valued for flashes of iridescent colour that seem to burn under its surface. Wikipedia says it occurs only in the south-western United States and in parts of northern and central Mexico. After a long period of heavy volcanic activity, hot water rich in silica and iron oxide seeped into cracks and hollows in the rock and set there as chalcedony interleaved with thin films of iron oxide; inclusions of goethite or limonite give the stone its brown body and its play of colour. Because it usually shows no banding, it is not strictly an agate at all, whatever its name. Its Mohs hardness of 6.5 to 7 means a polished stone stands up well to wear in jewellery. Hall links fire agate both to the earth's energy and to the fire element, crediting it with strong grounding powers and a calming, steadying influence. She calls it a protective stone that shields the body against ill-wishing and turns harm back on whoever sent it, and says it eases fear, prompts introspection and, by letting the body relax, deepens meditation. Hall also associates it with healing the stomach and circulation, and the endocrine and nervous systems, and with vitality and sexual energy; these are her claims, not established medicine.