A traveller of credit gives us an account, in the Philosophical Transactions, of a remarkable cave, some leagues to the north-west of Mexico, gilded all over with a sort of leaf-gold, which had deluded many Spaniards by its promising colour, but they could never reduce it into a body, either by quicksilver or fusion. This traveller went thither one morning with an Indian for his guide, and found its situation was pretty high, and in a place very proper for the generation of metals.

As he entered into it, the light of the candle soon discovered on all sides, but especially over his head, a glittering canopy of these mineral leaves, at which he greedily snatching, there fell down a great lump of sand, that not only put out his candle, but almost blinded him, and calling aloud to his Indian, who stood at the entrance of the cave, as being afraid of spirits and hobgoblins, it occasioned such thundering and redoubled echoes, that the poor fellow, imagining he had been wrestling with some infernal ghosts, soon quitted his statron, and thereby left a free passage for some rays of light to enter, and serve him for a better guide. The traveller's sight was somewhat affected by the corrosive acrimony of the mineral dust; but having relighted his candle, he proceeded in the cave, heaped together a quantity of the mineral mixed with sand, and scraped off from the surface of the earth some of the glittering leaves, none of which exceeded the breadth of a man's nail, but with the least touch were divided into many lesser spangles, and with a little rubbing they left his hand gilded all over.