Chalcedony- associated with sacral and solar plexus chakras. Colours vary from white to grey/greyish blue, or brown ranging from light brown to nearly black. Has a waxy lustre and may be semi-transparent to translucent. Chalcedony improves mineral assimilation and combats mineral buildup in veins which is said to lessen the effects of dementia and senility. Removes unwanted feelings of hostility and removes sadness and self doubt while building confidence. Balances mind, body, spirit and emotions.