Carbonate of Lime, var. metastatic

This fine yellowish crystal shows at the apex three polished faces, which are parts of the equiaxed crystals: several others next to them show the approach to the primitive rhomb, and three primitive faces; the rest is part of an unequal-sided or flattish metastatic. The double refraction is seen, when held in certain directios, by the prismatic tints, which are very beautiful, and in some positions catch the rays of light, so as to show them in great abundane in the numerous flaws; which flaws would be some detriment to the specimen, if this appearanace did not so well compensate for them. They also serve by their direction to show how the fragments are obtained which exhibit the nuclei. See tab. 2.