Mineral Guide > Mineral Gallery > Agate gem stone

Agate gem stone

Of the quartz family, and is one of the modifications in which silica presents itself nearly in a state of purity. Agates are distinguished from the other varieties by the veins of different shades of color which traverse the stone in parallel concentric layers, often so thin as to number fifty or more to an inch.

Externally the agates are rough and exhibit no appearance of their beautiful veined structure, which is exposed on breaking them, and still more perfectly after polishing.

Though the varieties of agate are mostly very common minerals in this country as well as in the old world, those localities only are of interest which have long been famous for their production and which still furnish all the agates required by commerce.

Agate picture