Carbonate of Lime

Llandidno in Denbighshire, North Wales, affords crystallized Carbonate of Lime in groat abundance, which is remarkable for being in the inverse rhomboidal form, and in the early part of this work was sufficient to attract, attention, and the more so as being coloured with Red Oxide of Iron. See tab, 4.

The present specimen shows a gradation with a distinct appearance of the facets, so placed as to commence a rounding form, more peculiar to this than any other place; and which may be very gradually traced to lose their sharpness, and to be as it were obliterated by passing imperceptibly nearly into a sphere. It is sufficient here to to show the corners with the bevillings at the alternate acute angles; and the three faces at the apex belonging to the obtuse rhomb, called Cuboide Haüy, v. 2, p. 138.

The crystals in this specimen are beautifully iridescent upon their surfaces, and there is a nearly octaëdral rusty Pyrites, Mountain Blue Copper, or Carbonate of Copper like Smalt, and some Green Carbonate of Copper, which gives the whole a handsome appearance for a picture.