Platinum
2 of the 6 encyclopedias on this shelf carry an entry for Platinum. Both are reproduced below, so you can see where they agree and where they differ.
Aiton's Encyclopedia (1910)
a heavy metal of a tin-white color. The name is derived from the Spanish and means silvery. Platinum may be hammered into thin sheets and drawn into slender wire. It is not inclined to unite with other elements but forms alloys with metals readily. It melts only at an exceedingly high temperature-3200 deg. F. Platinum crucibles and spoons are considered indispensable in the chemical laboratory. Platinum occurs in most gold-bearing gravels, but, as it does not amalgamate with mercury, it is difficult to collect. California and Oregon produce small quantities. The world's supply has been derived for centuries chiefly from the Siberian side of the Ural mountains , where it is associated with iron. Colombia exports platinum. Other producers are Brazil, Borneo, Australia, and New Zealand . The market value of platinum varies from $4 to $15 an ounce. Russia used to employ platinum alloy in hardening gold for coinage, but it is now too valuable for that purpose. Platinum pins are used to fasten artificial teeth to the plate, as it is the only metal that will stand the heat of baking. Platinum wires are used in electric lamps. Platinum is also in some demand for filling teeth, in photography, and in jewelry. An authority writing in 1903 states that the world uses 16,591 pounds a year. The Urals produce 10,500 pounds; other regions, 2,000. The deficit is made up by the use of old platinum. See Ductility
Collier's New Encyclopedia (1921)
in chemistry, symbol, Pt .; at. wt., 194.3; sp. gr. 21.6, a tetrad metallic element discovered first in the United States; still produced there; also found in the Ural chain, and in copper ore from the Alps. Pure forged platinum takes a high luster, is nearly malleable. as It silver resists, and the very strongest ductile heat and of the forge fire, but can be fused by the electric current; is the heaviest iridium, is unalterable in the air, disknown substance excepting osmium and solves slowly in nitromuriatic acid, but is not attacked by any single acid. It is used extensively in the manufacture of expensive jewelry, and delicate instruments. During and after the World War (1914-1918) it ranged in value from $120 to $150 per ounce.
What Has Changed in the Last Century
Both entries put the world's platinum in the Urals, with Aiton's in 1910 crediting Russia with 10,500 of the 16,591 pounds used annually. That map was redrawn in 1924, when Hans Merensky traced the platinum-bearing reef of South Africa's Bushveld Complex that still bears his name; South Africa and Russia's Norilsk deposits now supply the great bulk of the metal. The uses have shifted too: Collier's 1921 list of jewelry, dental work and laboratory ware has been overtaken by catalytic converters for vehicle exhausts, a market that has consumed most annual output since the 1970s. Collier's claim that platinum was "discovered first in the United States" is mistaken – it was worked by pre-Columbian metalsmiths in what is now Colombia and Ecuador and described for Europe by Antonio de Ulloa in the eighteenth century.
Written for this edition, 2026.