Blue-Gray Marble #177

This sample from Lucerne Valley, California, USA, contains both calcite and dolomite. The calcite is grayish with a very (!) light blue tinge; the dolomite is lighter - almost white. The two minerals are difficult to distinguish, both in hand specimen and in thin section, without using a chemical stain. Ward’s Scientific calls this a “blue-gray” marble, but it takes an active imagination to see the blue. Some marbles, including the classic marble from Crestmore, California (not far from Lucerne Valley), have a much stronger blue color. This sample is 10 cm in longest dimension.