Catalog Number:
41588
Specimen Count:
1
Precise Locality:

Aunor Mine

Locality:
Canada including Hudson Bay and Northwestern Passages
Collecting Locality:
North America, Canada, Ontario, Hastings County

In nature, only a few elements occur in their native form as a single, solid element, not chemically combined with others. Gold, the best known example, is less chemically active than most other elements that exist in solid form. Gold occurs as tiny particles in rocks; as hot water seeps through bedrock, it may carry the gold bits until they accumulate into small nuggets. A few other metals, such as silver and copper, are sometimes found in small standalone amounts in nature. Whether silver, copper, and platinum combine with other elements or remain as native elements depends on their proximity to other chemically active substances. A few nonmetallic elements also may occur in native form. For example, plain sulfur collects around the vents of hot springs and volcanoes, as well as in sedimentary structures like salt domes. In nature, carbon can appear in two different native forms, graphite and diamond, depending on how much heat and pressure have been applied to it.

Since antiquity, humans have made pottery from clay, which consists of fine particles of silicate minerals. Kaolinite is an aluminum silicate mineral, and it is the main component of porcelain, a particularly hard type of ceramic. Clay, which is used to make other types of pottery, may contain silica and grains from sedimentary rocks. Quartz, also referred to as silica or silicon dioxide, is a key component of another important solid material: glass. In the ancient Middle East, humans made glass by heating silica with alkali that was made from the ashes of plants. Other minerals such as calcium, lead, calcium, and manganese were added to improve the glass. Metals and metallic oxides were also added to color the glass or to make it clear, since natural glass tends to be slightly colored from impurities in the sand. Ruby red is made from powdered gold, while an orangey-red is produced by copper oxides. If the glass with copper oxide is heated too much, it will turn green. Cobalt and iron can make blue glass, and manganese is used for purple. Antimony or manganese oxide will produce clear glass. Glass for specialized purposes, like cookware and optical instruments, may require additives, such as boron oxide or lead oxide.

Shiny metals have been associated with beauty and wealth throughout human history. Gold, silver, and copper are three of the few metals that sometimes occur uncombined with other elements in nature, so it was relatively easy for ancient humans to collect them for personal adornment and trading. Copper jewelry emerged about 7,000 years ago, and the Egyptians began to make gold jewelry between 3,000 and 5,000 years ago. In many cultures, people put much of their wealth into their jewelry, both metallic and non-metallic (stones and bones), and used it as currency before the idea of money developed. The first coins appeared in the areas now known as Turkey and Greece about 2,600 years ago. Over the centuries, humans added so-called "base" metals to the gold and silver in coins, whose value became determined by law, not the actual value of the metals in the coin. Today, a U.S. "copper" penny is 97.5 percent zinc with a thin coating of copper; higher-denomination coins have a copper core covered with a copper-nickel alloy.