Turquoise
Turquoise has been used for jewelry and decoration for thousands of years. The turquoise on the right is typical turquoise, while the sample on the left has had the copper replaced by iron. Iron can also cause yellow turquoise. Turquoise is usually altered to improve either its color or hardness, as it is a porous mineral and easy to alter. Unaltered turquoise is hard to find. Color: Sky-blue, blue-green, apple-green Color of streak: White Moh’s hardness: 5-6 Density: 2.31-2.84 grams/cubic centimeter Cleavage: None Fracture: Conchoidal, uneven Crystal system: (Triclinic) seldom; grape-shaped aggregates Chemical composition: CuAl6(PO4)4(OH)8•5(H2O); a copper containing basic aluminum phosphate Transparency: Translucent, opaque Refractive index: 1.610-1.650 Double refraction: +0.040 Dispersion: None Pleochroism: ...
Sulfur
One of the most commonly known attributes of sulfur is its smell. Its infamous aroma is caused a reaction between the sulfur and water, creating hydrogen sulfide (H2S). Its most common use is the production of sulfuric acid but it is also used in fertilizers and other agricultural products, gunpowder, matches, detergents and preservatives for wine and dried fruit. Sulfur found naturally is written chemically as S8 as this allotrope of sulfur is most stable. Sulfur is the tenth most abundant element in the universe. The speckles in the upper right hand corner of the picture are small fragments of the sulfur. When ...
Rock Crystal
Rock crystal is the official name given to what most people call quartz ("Quartz" covers a large umbrella of different minerals. Varieties of quartz are distinguished only by differences in the individual crystals on a molecular level). It is the most common mineral on the planet, since most sand and other rocks are made of rock crystal. One interesting thing about rock crystal is that it is piezoelectric. This feature gave rock crystal's first commercial success as phonograph needles. It is most commonly used today in watches, internal clocks for computers and as frequency stabilizers for radio transmitters. Color: Colorless Color ...
Pyrite
Pyrite is most commonly known as “Fool’s Gold”. Pyrite is a secondary source for sulfur. During WWII, deposits of iron pyrite were mined for its sulfur and iron. Pyrite could be used as an ore for iron, but hematite and magnetite are more economical to mine and therefore they are primary ores. The brightly colored reds, blues and greens are an optical anomaly. They are not a characteristic of pyrite under normal viewing conditions. Color: Brass-yellow, gray-yellow Color of streak: Green-Black Moh’s hardness: 6 to 6 1/2 Density: 5 to 5.2 grams/cubic centimeter Cleavage: Indistinct Fracture: Conchoidal, uneven, brittle Crystal system: Cubic, pentagonal, dodecahedra, octahedral Chemical composition: ...
Amethyst
Amethyst is the most valuable variant within the quartz family. The crystals are always anchored to a base. The base is usually agate. The purplish color of this sample of amethyst is caused by atomic impurities found inside the crystal. Geologists do not know what these impurities are, but manganese, iron and sulfur are likely culprits. Amethyst can be found in geodes and alluvial deposits. Color: Purple, violet, pale red-violet Color of streak: White Moh’s hardness: 7 Density: 2.65 grams/cubic centimeter Cleavage: None Fracture: Conchoidal, very brittle Crystal system: Hexagonal prisoms Chemical composition: SiO2, silicon dioxide Transparency: Transparent Refractive index: 1.544-1.553 Double refraction: +0.009 Dispersion: 0.013 (0.008) Pleochroism: Weak, reddish-violet, gray-violet Absorption spectrum: ...
Biology
How to Build a Compost PileCompost piles are piles of organic waste that are decomposed in a relatively controlled... [Read more]
Read More Posts From This CategoryChemistry
Manufacturing Sodium AcetateSodium acetate, apart from being a food additive and a base used to neutralize sulfuric... [Read more]
Read More Posts From This CategoryGeology
TurquoiseTurquoise has been used for jewelry and decoration for thousands of years. The turquoise on the right is typical turquoise, while the sample on the left has had the copper replaced by iron. Iron can also cause yellow turquoise. Turquoise is usually altered to improve either its color or hardness, as it is a porous mineral and easy to alter. Unaltered... [Read more]
SulfurOne of the most commonly known attributes of sulfur is its smell. Its infamous aroma is caused a reaction between the sulfur and water, creating hydrogen sulfide (H2S). Its most common use is the production of sulfuric acid but it is also used in fertilizers and other agricultural products, gunpowder, matches, detergents and preservatives for wine... [Read more]
SodaliteSodalite is a rare mineral. Hackmanite is an important variety of sodalite exhibiting tenebrescence. Originally discovered in 1806, it was not until vast deposits of good grade sodalite were found in Ontario that it became popular. It is used for ornamental objects, such as cabochons, beads and carved animals. Color: White, blue and grey Color of streak:... [Read more]
Rock CrystalRock crystal is the official name given to what most people call quartz (”Quartz” covers a large umbrella of different minerals. Varieties of quartz are distinguished only by differences in the individual crystals on a molecular level). It is the most common mineral on the planet, since most sand and other rocks are made of rock crystal. One... [Read more]
PyritePyrite is most commonly known as “Fool’s Gold”. Pyrite is a secondary source for sulfur. During WWII, deposits of iron pyrite were mined for its sulfur and iron. Pyrite could be used as an ore for iron, but hematite and magnetite are more economical to mine and therefore they are primary ores. The brightly colored reds, blues and greens are... [Read more]
AmethystAmethyst is the most valuable variant within the quartz family. The crystals are always anchored to a base. The base is usually agate. The purplish color of this sample of amethyst is caused by atomic impurities found inside the crystal. Geologists do not know what these impurities are, but manganese, iron and sulfur are likely culprits. Amethyst... [Read more]
Read More Posts From This Category