Chalcedony has a waxy luster, and may be semitransparent or translucent. It can assume a wide range of colors, but those most commonly seen are white to gray, grayish-blue or a shade of brown ranging from pale to nearly black.
The mineral gets its name from the town of Chalcedon.
The hardness (Mohs scale) : 6.0 - 7.0
The following free streaming videos are form www.youtube.com
Stores from www.amazon.com The product categories are under 'powered by amazon.com' (right rectangle) Please read the product details carefully before purchase.