The shores of the Paraguay and other rivers afford gypsum. The Guaranies, who dwell at a distance from these shores, make use of burnt snails' shells, or of a chalk like fuller's earth, which they call _tobaty_, in whitening their houses. At the banks of the greater Tebiguarỹ, I sometimes saw marble of a black colour, spotted with green, but of very small dimensions. I know not whether any other marbles or remarkable stones are concealed in the bosom of the earth elsewhere. Red and black flints, containing plenty of fire, and extremely fit for muskets, may be seen in many places, especially at the banks of the Uruguay; but instruments to cut them, and fit them for the use of muskets, are wanting. Whether Paraguay produces alum, sulphur, and mercury, I do not know. Many have committed mistakes who have written concerning Paraguay, in that country itself. They have liberally bestowed treasures upon it, not because it really possesses them, but because they have dreamt of them in a country utterly destitute of all metals. The blind man dreamt that he saw, as the Spanish proverb goes, and he dreamt of what he desired. _El çiego soñaba que veia, y soñaba lo que queria._ To this number belongs Martin del Barco, Archdeacon in the city of Buenos-Ayres, who, in his poem intituled _Argentina, y Conquista del Rio de la Plata_, affirms that pearls are formed in some lake, near which the Abipones inhabit. The oldest of the Indians, the most distinguished for experience and veracity, who were born in that neighbourhood, and had dwelt there for many years, all answered, with one accord, that they had never seen any pearls, nor heard any thing about them from their ancestors. Would not these savages, who continually adorn their necks, arms, and legs, with glass beads brought from Europe, with little round globes made of cockle-shells, with the seeds and kernels of various fruit and the claws of birds, would not they have grasped eagerly at pearls, which are naturally so bright, had they ever met with any? We may therefore safely pronounce this lake, said to produce pearls, a mere fable, long since expunged from history by all sensible persons. Silver vessels are seen in the houses of the Spaniards, and silver utensils in the churches of the cities. In the Guarany colonies, not only the altars, but sometimes the very ceilings are gilded. This I do not deny. But all that gold and silver was not created in the bowels of Paraguay, but brought from the provinces of Chili or Peru. The Guaranies make very large brass bells for their own churches, or for those of the Spaniards; but the people of Chili supply them with brass. No money is coined in any part of Paraguay in the name of the King, or of any other person.