As a relatively rare metal, sometimes classified as a metalloid, Bismuth is found in the earth's crust at about the same abundance as silver, and is usually associated with copper, lead, tin, wolfram (an important tungsten ore), silver, and gold ores.
The most common bismuth minerals are bismuthinite and bismite.
Generally, these and other bismuth minerals occur in minute quantities within
ores of other metals, such as gold, silver, lead, zinc, and tungsten
Interestingly, while these decorative crystals can and do form naturally, they can also be created through heating the clean bismuth and then slow cooling it. They can also be manipulated by the cooling rate, which affects the size and structure of the resulting crystals—the slower the cooling, the larger the crystals.
The difference in colors results from the variations in the thickness of the oxide layer on top of the crystal, thus causing direct light on the crystals to form variations of different light wavelengths that disrupt the reflection, which provides their beautiful rainbow effect.
In their final stages, the bismuth provides beautiful decorative properties that anciently were used solely for decoration because of their shimmering iridescent colors. Anciently it was called tectum argenti, meaning “silver being made,” and was thought of as a “half-way form of silver,” that is, in the process of being formed but not yet finished. In ancient Andean Peru, where the metal is predominantly found, while the ancient name has been lost, it was used as late as the Incas for decoration, and found in burial chambers as a special bronze alloy for their knives. It was also used with bronze, and though bismuth can make bronze brittle, the ancient Peruvian smiths learned how to use it to give bronze new properties without such embrittlement (Robert C. Cowen, “Ingenious Metalsmiths,“ The Christian Science Monitor,1984).
Sican ceremonial tumi knife, distinctly characterized by a
semi-circular blade, made of either bronze, copper, gold-alloy, wood, or silver
alloy and is often inlayed with semi-precious stones such as lapis lazuli.
Tumis are most often associated with Pre-Inca cultures in the Peruvian Coastal
Region
Bismuth is one of the few materials that has a greater density as a liquid than as a solid, and when melted, can be poured into virtually any shape, from thin sheet layers to thick ingots where it solidifies once again. In ancient Egypt it was found to be mixed with copper in thin sheets to decoratively cover wood (Alfred Lucas and J.R. Harris, Ancient Egyptian Materials and Industries, Dover Publications, New York, 1929, p216). Today, in addition to Peru, major producers of Bismuth are Bolivia, Mexico, Japan and Canada.
Versatile bismuth. Top Left:
The lusters on the vases result from a particular metal amongst their various
constituents: orange luster based on iron: yellow on uranium; mother-of-pearl
despite its multi-color effect from only one metal, titanium or bismuth; Top
Middle and Right: Bismuth in settings, small and large; Bottom: Pure bismuth
metal ingots
It also has a very low thermal conductivity—lower than any other metal except mercury, and has a relatively low melting point, especially when alloyed with tin and lead. Bismuth burns with a blue flame and clouds of yellow oxide when heated in air (“The History and Use of Our Earth’s Chemical Elements: A Reference Guide,” Greenwood Publishing Group, 2006).
When liquid bismuth freezes, it expands rather than contracts because it forms a crystalline structure similar to water—only four other elements expand when they freeze: silicon, gallium, antimony and germanium.
The name bismuth was probably taken from two German words, weisse masse, meaning "white mass," describing how the element appears in nature. Later the name was shortened to wismuth, and then to bisemutum, before bismuth came into common use. It is a soft, silvery metal with a bright, shiny surface and a yellowish or pinkish tinge, and the metal breaks easily so it cannot be fabricated (worked with) at room temperature. Its melting point is 520°F., though some bismuth alloys melt at 158ºF., and its boiling point is 2,847°F (58 of the 94 elements that have boiling points, have boiling points higher, such as lead with a boiling point of 3164ºF. (melting point 621º), with silver, tin, aluminum, copper, nickel, iron, gold, etc., even higher (though tin has a lower melting point)—carbon, needed to mix with iron to make steel, has a boiling point of 8720ºF).
All of this suggests that bismuth is easy to work with as an alloy, and can be melted and poured into molds that have any shape or size, and as it cools, unlike most metals, it expands (instead of contract) as it solidifies (changes from a liquid to a solid), and in so doing it fills all the corners of the mold. Though it is relatively rare in the Earth (0.2 parts per million, about twice as abundant as gold), it is plentiful in China, Mexico and Peru (world mining production in 2010 was 8,900 tonnes, with the major contributions from China: 6,500 tonnes; Peru: 1,100 tonnes; and Mexico: 850 tonnes), and typically found with lead, silver and gold.
However, the major ores of bismuth: bismuthinite (the sulfide), also called bismuth glance, and bismite (the oxide) are found extensively in South America, and are rare in the U.S. and Mexico. In fact, Peru is one of the world’s top mineral producing countries, extracting from the rich mountains gold, silver, copper, zinc, lead, tin, arsenic trioxide and minerals like bismuth and molybdenum.
A unique Julcani
District, Peru mineral specimen - Bismuth Sulfosalts with Chalcopyrite,
Tetrahedrite, and Siderite on Pyrite. Peru has many such Bismuth oddities
The other suggestion by scholars for the term “ziff” is “platinum,” a name that comes from the Spanish word “platina,” meaning “little silver,” and requires 6920ºF to boil and has a melting point of 3222ºF. Not discovered until the middle of the 16th century, Julius C. Scaliger wrote about it in 1557, describing it as “a strange metal found in mines between Panama and Mexico,” and also stated that “no fire or any of the Spanish arts could melt it.”
In 1783 French chemist Francois Chabaneaus discovered and patented a method of producing workable platinum, though the quality of the metal was inconsistent from batch to batch, because as later learned, there were impurities of undiscovered metals—later discovered osmium iridium rhodium and palladium. By the middle of the eighteenth century, its use in decoration was to provide a silver luster or iridescence on ceramics, a process known since around 900 A.D. in which silver and gold were used. With the invention of electroplating in 1840s, this process, using platinum, fell into disuse.
It seems unlikely that platinum would actually qualify as “Ziff” used for decoration by Noah in the last century B.C. This leaves only Bismuth as a practical metal that fits the description in the scriptural record—a metal found in abundance in Peru.
Do we know what Ziff is for certain? No. However, there are few other possibilities in the metals field that meet the suggestive purpose outlined in Mosiah. Bismuth seems to be the only semi-precious metal (comparatively rare) that would be used for decorative purposes as is shown in Mosiah.
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