Carbonate of Lead

Carbonate of Lead of this form and colour has for many years been considered as a Molybdate. Its readily effervescing in dilute Nitric Acid will, however, betray it. The modifications of the present specimen are remarkably striking, and are evidently to be traced from, or to, the plated forms of tabs. 89, 90, and 91. The Crystals have a light glare, and somewhat pearly lustre, and are in colour from nearly white to greenish yellow; scattered in irregular fissile hexangular plates, or more compact:—see the middle figure, which contains plates nearly like the lower left hand outline, or piled up as that on the right hand.

These specimens are very rare. and occur only now and then til the Wanlock-head mines near Glasgow, I have one from Mr, Day’s collection, some years old; and some by means of other friends. I do not know that they are found elsewhere, or are at all described as green, or approaching thereto. They are said to be snow-white, grayish and yellowish-white, cream-yellow, and clove-brown.