Alluding to the ill-success attending the experiment performed by Ambroise Paré, in order to test effectively the supposed virtues of the substance as an antidote for poisons, Engelbert Kaempfer remarks that Paré’s bezoar may have been of inferior quality, and, moreover, bezoars could not be successfully used to counteract mineral poisons, but were only useful when vegetable poisons had been taken. This opinion was probably due to the fact that the bezoar itself is largely or in the main a vegetable substance. That the interior layers of a specimen should be inferior in quality to the external layers was not for Kaempfer a proof of its spurious character, but might easily be accounted for by a change of pasturage in the case of the creature in whose body the concretion had formed. This writer asserts that he considered those bezoars to be genuine which were of a partly resinous and partly mineral composition, so that when pulverized they could be dissolved in nitric acid, the solution having a reddish hue. The Persians not only attributed to bezoars the same virtues as did the Europeans, but also recommended the administration of the bezoar elixir to persons in health, that they might avoid contracting disease and prolong their lives, more especially if the dose were taken at the beginning of the year. In general, however, he found that where Europeans used the bezoar as a remedy, the Persians gave a dose of pearl tincture instead; but as rarities, or perhaps as talismans, bezoars were even more highly prized in Persia than in Europe, for there was hardly a Persian of note who did not preserve one of these concretions among his treasures. The price depended upon perfection of form and color, as well as upon size, one weighing a mishkel (about 75 grains Troy) was commonly valued at one toman, the equivalent of 15 ounces of silver (about $20), according to Kaempfer’s computation, but the price rose rapidly with the size of the bezoar in a proportion similar to that observable in the case of pearls. As Persian bezoars were so costly in Persia, and the home demand for them so great, those sold by this name in Europe must have had another origin.[418]