Sulphate of Barytes

This specimen has so much the appearance of moss, that it is very likely to be taken for a moss covered with or replaced by Carbonate of Lime, like plate 346, but is really crystals of Sulphate of Barytes, mostly of the primitive form, piled like foliage, sometimes a little rounded, and as it were accidentally disposed in more or less regular branches, and may be compared to the quadrangular imbrication of Erica vulgaris, the Common Heath. Eng. Bot. tab. 1013, especially when bushy and before flowering, and is found in rather dense masses like it. I find Woodward had a similar comparison, but have not the work to quote.

This substance affords much variety. Perhaps this with what has been already done will be sufficient examples in this work, except the remainder of the modifications of its crystals in one plate.

It was of consequence to have such a specimen as this, to instruct us not too freely to take these resemblances for petrifactions, i. e. organized bodies, whether animal or vegetable, wholly or in part displaced by stony substances. The knowledge of crystallization shows that the form depends upon the aggregate of crystals accumulating in peculiar order.