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mines of platina, or the exportation of platina lying atday, or both j we may observe, that the setting at largeeven of the little quantity that has hitherto been madepublick, far from being productive of any ill consequences,has been the means of effectually preventing those abuses,which platina could not fail of giving occasion to, whileconfined to a particular part of the world, and while theexistence of such a substance was in general unknown. Inthe papers laid before the royal society soon after the pla-tina came here, there is an account of gold having beentaken in payment from some Spaniards,which being mixedwith platina was so brittle that it could not be disposed of,and which could not be refined in London, so that it wasquite useless. I have been informed that the Dutch re-finers at Dort have long complained of their meeting withgold adulterated with a substance which they could not se-parate, which they called diabolus metallorum, and whichthey now judge to have been no other than platina; andthat our jewellers, &c. for many years past, have avoidedmaking use of the Spanish gold for any curious works, onaccount of its having frequently a mixture of a substancewhich renders it intractable, and which is often visible tothe eye in small distinct grains like those of platina, as ifthe gold had been melted by a heat not sufficient for theperfect dissolution of the platina, which when dissolvedwould have given an ill colour to the mass (fee page 526).The more the platina became known, the less danger therewas of any frauds of this kind, and we have now nothingto fear from it; the experiments already made having dis-covered easy means of distinguishing with certainty gold de-based by platina, and of completely parting the two metals,however they may be blended together by accident or de-sign. The refining of gold from platina is now no more•difficult than the refining of it from any other metal.

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