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Galena

$19.00 – $400.00

Galena is the main ore of lead, used since ancient times. Because of its somewhat low melting point, it was easy to liberate by smelting. It typically forms in low-temperature sedimentary deposits.

In some deposits galena contains about 1–2% silver, a byproduct that far outweighs the main lead ore in revenue. Galena deposits often also contain significant amounts of silver as included silver sulfide mineral phases or as limited solid solution within the galena structure. These argentiferous galenas have long been the most important ore of silver.[citation needed]

Galena deposits are found worldwide in various environments. Noted deposits include those at Freiberg in Saxony; Cornwall, the Mendips in Somerset, Derbyshire, and Cumberland in England; the Madan, Rhodope Mountains in Bulgaria; the Sullivan Mine of British Columbia; Broken Hill and Mount Isa in Australia; and the ancient mines of Sardinia. Galena also occurs in North African countries and at Mount Hermon in Northern Israel. In the United States, it occurs most notably in the Mississippi Valley type deposits of the Lead Belt in southeastern Missouri, and in the Driftless Area of Illinois, Iowa and Wisconsin. The economic importance of galena to the early history of the Driftless Area was so great that one of the towns in the region was named Galena, Illinois.

Cubic galena with calcite from Jasper County, Missouri, USA; 5.1 cm × 3.2 cm × 2.8 cm (2.0 in × 1.3 in × 1.1 in)

Galena also was a major mineral of the zinc-lead mines of the tri-state district around Joplin in southwestern Missouri and the adjoining areas of Kansas and Oklahoma. Galena is also an important ore mineral in the silver mining regions of Colorado, Idaho, Utah and Montana. Of the latter, the Coeur d’Alene district of northern Idaho was most prominent.

Galena is the official state mineral of the U.S. states of Missouri and Wisconsin; the former mining communities of Galena, Kansas and Galena, Illinois take their names from deposits of this mineral.

Derbyshire in the UK was one of the main areas where galena was mined.

The largest documented crystal of galena is composite cubo-octahedra from the Great Laxey Mine, Isle of Man, measuring 25 cm × 25 cm × 25 cm (10 in × 10 in × 10 in).

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Silk Fiber

$19.00 – $400.00

Silk is a natural protein fiber, some forms of which can be woven into textiles. The protein fiber of silk is composed mainly of fibroin and is produced by certain insect larvae to form cocoons.[1] The best-known silk is obtained from the cocoons of the larvae of the mulberrysilkworm Bombyx mori reared in captivity (sericulture). The shimmering appearance of silk is due to the triangular prism-like structure of the silk fibre, which allows silk cloth to refract incoming light at different angles, thus producing different colors.

Silk is produced by several insects, but generally only the silk of moth caterpillars has been used for textile manufacturing. There has been some research into other types of silk, which differ at the molecular level.[2] Silk is mainly produced by the larvae of insects undergoing complete metamorphosis, but some insects such as webspinners and raspy cricketsproduce silk throughout their lives.[3] Silk production also occurs in Hymenoptera (bees, wasps, and ants), silverfish, mayflies, thrips, leafhoppers, beetles, lacewings, fleas, flies, and midges.[2] Other types of arthropod produce silk, most notably various arachnids such as spiders.

 

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Parson Spider

$19.00 – $400.00

The spider species Herpyllus ecclesiasticus is commonly called the eastern parson spider, after the abdominal markings resembling an old-style cravat worn by clergy in the 18th century

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Salticidae on Water 5x

$19.00 – $400.00

The jumping spider family contains more than 500 described genera and about 5,000 described species, making it the largest family of spiders with about 13% of all species.

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Salticidae on Water

$19.00 – $400.00

The jumping spider family contains more than 500 described genera and about 5,000 described species, making it the largest family of spiders with about 13% of all species.