Rhodonite is an opaque, deep-rosy-pink-to-lavender gemstone with characteristic black veins called dendrites. Composed of manganese silicate, it makes a more durable gemstone than rhodochrosite, which is reactive to acids. Rhodonite, on the other hand, does not react to acids and is usually associated with black manganese minerals and pyrite. Most cleaning methods are safe for rhodonite (ultrasonic, etc), but like with all gemstones, avoid rough handling and extreme heat. Sometimes called the "the singer's stone," rhodonite is said to improve sound sensitivity. Many also believe it to help with the nervous system and self-esteem, and to balance trauma. It has long been considered a strong, feminine stone, as in the velvet glove over the iron fist. Natural healers associate rhodonite with the throat chakra (fifth), to help one achieve potential and dispel worry. Important sources of this gemstone include Brazil, Mexico, Peru and Colorado (U.S.A.).