Post by 1dave on May 10, 2019 10:49:32 GMT -5
A good start on geology and Oregon:
catalog.extension.oregonstate.edu/sites/catalog/files/project/pdf/4-h3401l.pdf
In the References are gems like:
Geitgey, R.P., 1987a, Mineral industry in Oregon, 1986: Oregon Geology, v. 49, no. 4, pp. 43–46. —1987b, Oregon sunstones: Oregon Geology, v. 49, no. 2, pp. 23–24.
Sunstones
This PDF is chock full of newspaper articles etc.
catalog.extension.oregonstate.edu/sites/catalog/files/project/pdf/4-h3401l.pdf
Zircon, ZrSiO4—an ore of zirconium and hafnium(Pronounced “zur ́‑con”; from Arabic zarqun, from Persian zar—gold and gun—color)Zircon is a chemical combination of the elements zirconium, oxygen, and silicon. When found in sands, it is usually in small, clear, pointed rectangular crystals. It is quite hard (H = 7.5) and has a specific gravity almost twice that of quartz. Therefore, it is frequently found associated with the heavier, dark‑color minerals.
Generally, zircon fluoresces a distinctive bright golden yellow under ultraviolet light, probably because of the presence of a small quantity of the element hafnium. Zircon is a common accessory mineral in igneous rocks, especially those that are high in quartz.A process for obtaining metallic zirconium and hafnium from zircon sands was developed by the U.S. Bureau of Mines at their Northwest Electro‑development Laboratory at Albany, Oregon, now the Albany Research Center. Metallic zirconium is used in nuclear power plants; in the making of special steel alloys, vacuum tubes, flashbulbs, and pyrotechnics; and in construction for chemical plants. Hafnium, which is very expensive, is used for control rods in nuclear power plants.
Nonmetallic minerals _________________________ (Minerals lacking the properties of metallic minerals)
Agate, SiO2(Pronounced “ag ́‑it”; from the locality in the ancient river Achates, now Carabi, in Sicily)Agates are rather common “pretty stones.” Chemically, they are composed of the same elements that combine to form quartz; that is, silicon and oxygen.
Agates are very finely crystalline and therefore are technically the form of quartz called chalcedony (pronounced “kal‑said ́‑o‑nee”). The bands so commonly seen in agates are edges of layers deposited in irregular cavities when the agate was being formed. The different bands and colors represent impurities and different periods of deposition in the filling of the cavity. The waviness of the lines is due to the irregularities in the cavity.
The “moss” commonly seen is due to fernlike growths of some mineral, such as manganese oxide or iron oxide minerals.The formation of agates requires solutions rich in silica. Therefore, they are more likely to be found in areas of more siliceous rocks such as rhyolites and dacites. Agates are not confined to rhyolite and dacite areas in Oregon, but many of the best collecting localities are found in rocks of this type.
Agates are found in practically every locality in the state. A few of the areas known for their quality and abundance are the coast; the Agate Desert northwest of Medford; Antelope Valley in north‑central Oregon; and the “thunder egg” localities of Wasco, Jefferson, Harney, Crook, Deschutes, Malheur, and Lake counties. The Richardson Ranch in Jefferson County is one of the most famous agate localities in the U.S. Oregon has long been known as a source of quality agates, and there are many people who come to the state each year just for collecting purposes. Thousands of “rock hounds” in the state have as their hobby the collecting, cutting, and polishing of local stones. Also, many residents of the state owe their livelihood to the sale of agates, both as raw cutting material and as the finished product. Oregon’s annual production of rough and cut gems has been estimated to be on the order of approximately $1 million.
The Oregon State Rock is the thunder egg, an agate‑filled nodule.
Generally, zircon fluoresces a distinctive bright golden yellow under ultraviolet light, probably because of the presence of a small quantity of the element hafnium. Zircon is a common accessory mineral in igneous rocks, especially those that are high in quartz.A process for obtaining metallic zirconium and hafnium from zircon sands was developed by the U.S. Bureau of Mines at their Northwest Electro‑development Laboratory at Albany, Oregon, now the Albany Research Center. Metallic zirconium is used in nuclear power plants; in the making of special steel alloys, vacuum tubes, flashbulbs, and pyrotechnics; and in construction for chemical plants. Hafnium, which is very expensive, is used for control rods in nuclear power plants.
Nonmetallic minerals _________________________ (Minerals lacking the properties of metallic minerals)
Agate, SiO2(Pronounced “ag ́‑it”; from the locality in the ancient river Achates, now Carabi, in Sicily)Agates are rather common “pretty stones.” Chemically, they are composed of the same elements that combine to form quartz; that is, silicon and oxygen.
Agates are very finely crystalline and therefore are technically the form of quartz called chalcedony (pronounced “kal‑said ́‑o‑nee”). The bands so commonly seen in agates are edges of layers deposited in irregular cavities when the agate was being formed. The different bands and colors represent impurities and different periods of deposition in the filling of the cavity. The waviness of the lines is due to the irregularities in the cavity.
The “moss” commonly seen is due to fernlike growths of some mineral, such as manganese oxide or iron oxide minerals.The formation of agates requires solutions rich in silica. Therefore, they are more likely to be found in areas of more siliceous rocks such as rhyolites and dacites. Agates are not confined to rhyolite and dacite areas in Oregon, but many of the best collecting localities are found in rocks of this type.
Agates are found in practically every locality in the state. A few of the areas known for their quality and abundance are the coast; the Agate Desert northwest of Medford; Antelope Valley in north‑central Oregon; and the “thunder egg” localities of Wasco, Jefferson, Harney, Crook, Deschutes, Malheur, and Lake counties. The Richardson Ranch in Jefferson County is one of the most famous agate localities in the U.S. Oregon has long been known as a source of quality agates, and there are many people who come to the state each year just for collecting purposes. Thousands of “rock hounds” in the state have as their hobby the collecting, cutting, and polishing of local stones. Also, many residents of the state owe their livelihood to the sale of agates, both as raw cutting material and as the finished product. Oregon’s annual production of rough and cut gems has been estimated to be on the order of approximately $1 million.
The Oregon State Rock is the thunder egg, an agate‑filled nodule.
In the References are gems like:
Geitgey, R.P., 1987a, Mineral industry in Oregon, 1986: Oregon Geology, v. 49, no. 4, pp. 43–46. —1987b, Oregon sunstones: Oregon Geology, v. 49, no. 2, pp. 23–24.
Sunstones
This PDF is chock full of newspaper articles etc.
