Chris’ Mineral & Opal Page

Minerals are fascinating things. There is so much to learn about them and their interesting uses. Hello, and welcome to Chris’ mineral page. On this page you’ll learn a lot about the certain mineral I individually researched (opal) along with other helpful information about minerals in general. From their majestic beauty to their chemical composition, information galore about opal and minerals in general is waiting at your fingertips, so join me as we explore the world of minerals.
Minerals are where we get the world’s metals, gems, and other materials that we use today to make many useful products. They are even found in every day things like our food, fertilizers, and medicines. Gemstones are usually used for show in jewelry, but can also be helpful for mechanical tools, such as diamond tipped drill bits. Metals are useful for lots of things such as wires and bars. Something as small as a metal light bulb filament and as big as the frame of a skyscraper all originated from metal minerals.

All minerals including opal must be not made of living organisms or "inorganic". Minerals are always solid with a definite volume and shape. Never will you find a liquid or gas that you could identify as a mineral. A mineral has a repeating pattern that gives it a crystalline structure. Thusly the mineral’s structure is "crystal". All minerals are formed naturally, and aren’t made by mankind. Minerals are made of chemical compounds and have a definite chemical composition. This means they form when 2 or more elements combine to form a compound. Opal is a hardened silicate gel in the quartz family. This means it is dried out silica gel. Opal’s chemical composition is SiO2H20.
There is several ways to identify such minerals as Opal. One is by its color. This method is rather faulty because the same mineral can come in a variety of colors. Opal for example can be black (black opal), red/orange (Mexican fire opal), transparent (jelly opal), multicolored (precious opal), white (white opal), etc. Factors such as weathering and impurities make color a poor indicator of a mineral’s identity. Luster is the way that a mineral reflects light. Luster is how shiny or dull the mineral is. There are 3 types of luster as follows: metallic, sub-metallic, and nonmetallic. Each is slightly less metallic than the other. Opal is nonmetallic because it has different colors and not a metal like appearance. Opal’s luster can be described as greasy, waxy, and oily. Streak is an even better way to identify a mineral, because a mineral’s color may vary, its streak wont. Streak is the color of a mineral’s powder when rubbed across an unglazed streak plate. Opal’s streak is white. Cleavage is the way a mineral breaks along a flat surface and fracture is when minerals break unevenly along curved or abnormal surfaces. Opal has no cleavage but it does fracture. Hardness is a minerals resistance to being scratched. On Friedrich Moh’s Hardness Scale opal rated a 5.5 to 6.5. This means the first of ten minerals to scratch opal was apatite & orthoclase. The 4 before it that opal was resistant to were #1: talc, #2: gypsum, #3 calcite, and #4: fluorite. There are 10 levels of hardness on Moh’s scale. Another indicator of a mineral’s identity is its density. Density is the measure of how much matter is in a certain amount of space. Density can be found by using a triple beam balance. Density is equal to mass over volume. It is measured by grams per centimeters cubed (g/cm3). Opal’s density is 1.9-2.5 g/cm3. There are also special properties that minerals can have. These are: optical properties, taste, magnetism, radioactivity, chemical reactions, and fluorescence. Opal is fluorescent under UV light such as a black light. It can glow anywhere from neon purple to neon green. Fluorescence is the only special property opal has. Optical properties cause double image when you look through the mineral. Minerals with radioactivity are radioactive and very dangerous. Minerals that have chemical reactions efferuesce or "fizz" when placed in acid or when weak acid is placed on the minerals surface. Opal is insoluble to acids, or "acid-proof". Some minerals are naturally magnetic and attract iron. Some minerals have a salty taste to them! I my self would try to identify a mineral another way before tasting it. Icky!
Opal has often been called the 5th of the precious gemstones, the other 4 being diamonds, emeralds, sapphires, and rubies. Opal is also known internationally as on the most exciting minerals because of its rarity and beauty. Opal being made 30% of water and, also a

Silicate gel is extremely sensitive to dehydration. When it is heated it dries out, cracks, and ultimately morphs into quartz (Note: opal itself is a type of quartz). Opal jewelry needs special care because of its fragile nature.

Opal is the national gemstone of Australia where more than 95% of the world’s precious opal is found. Opals were common in roman times when they mined in Rome mines in and near Cervenica and Czechoslovakia. It has also been mined in the Swedish regions of Mossgruvan, Ljusnarsberg, Vastmanland, Nordmark, Varmland, and the Taberg & Calcedone mines in Sweden. It’s also mined in the good old U.S. of A.! Specifically: Spencer, Idaho (Spencer opal) and Virgin Valley, Nevada (Virgin Valley opal). Its also mined in the West Indies in the country of Honduras. It also is found in Brazil, Mexico, and southern Africa.

Most of the world’s opal formed 60 million years ago in the cretaceous period when dinosaurs ruled earth and mammals were beginning to evolve. The current deserts in Australia now were the Inland sea in the cretaceous period. Here silica rich sediment washed up on the shoreline. After 30 million years of weathering, the Inland sea became the Artesian Basin. During all this weathering the silica rich sediment squeezed into the cracks of rocks, layers of clay, and even fossils. Some of the silicate solution became precious opal over time. Silica is one of few minerals that are sedimentary in origin. The water found in Australian opal, is that of the extinct Inland Sea.

Opal itself is quite interesting. It’s used as birthstones and in ancient witchcraft. Opal is the star stone for anyone who is and Aquarius or a Libra for your horoscope. It’s the birthstone for April (mystical birthstone), June (other birthstone), and October (modern and ayurvedic birthstones). It is also the anniversary gemstone for a couple’s 14-18th years of marriage. Opal in Latin is opalus, which means "Seeing Jewel". High quality opal is sometimes worth up to $20,000 more per carat than a diamond would be. In ancient times it was seen as a symbol of confidence and faithfulness. In Arabia opal was believed to have fallen from heaven in bolts of lightning, thus its amazing color. In the Middle Ages it was called "eye stone" because it was believed that it helped your eyesight. Blonde women wore opal jewelry in hope that their beautiful hair wouldn’t lose its color. Opals are great for ritual magic or witchcraft because they contain the color of every other birthstone, and can supposedly be charged with the energies and powers of all those stones. It can also be used in place of any birthstone in spells because of all its colors. It is said to be able to make things invisible and you can supposedly use it to se your past lives. Each color representing one of your past lives. White opal is used in full moon rituals to bring the powers of the moon goddess to its user. Fire opals are said to have great money drawing powers. I personally think all that is rubbish, but interesting rubbish at that. Even the Aztec’s mined opal in central and South America for their rituals.

As you can see there is a lot to be learned about minerals such as opal. They are truly magnificent things. I hope you’ve enjoyed reading my page, and I hope you return soon. My page has lots of helpful information to help you with. If your learning about minerals and school and need some helpful info, or if your just trying to identify a mineral, Chris’ Mineral & Opal Page is the place to be!