Carbonate of Lime

The present modification is far from common, and has so peculiar an appearance that it must attract the observation of the enlightened enquirer, showing how infinitely various may he the modifications of this substance. The edges of the three sides of the column are rounded by repeated facets on that and on the pyramid, and the other three sides of the column are Devilled laterally towards the former three, making" with them and the pyramid a figure like the front of a Gothic arch. The thickness of the column, and depth in the proportions of the flatter, or rounding, facets, give this a variable appearance. The pyramidal ends are often distinct, and nearly correspond with the primitive rhomb.