While an opal is opaque and white, displaying an iridescent play of colors in every color of the rainbow, the Mexican fire opal is transparent to translucent, with a uniform red, orange, yellow, or brownish body color.
Iron content is what gives Mexican fire opals their orange color.
Physically, it is said to have the power to heal the lower back, kidneys, and can stimulate sexual organs. Mentally, the fire opal is said to be a wonderful stone for those people who are shy and lack self-confidence.
The fire opal is also said to be able to help those who have just suffered from abusive relationships.
As the stone is said to be able to heal and relieve memories of rape, incest and sexual abuse, it also encourages positive and healthy sexuality and relationships.
Fire opals are extremely fragile, and suffer from changes in humidity, temperature, and even light.