Rocks, Minerals, and Gemstones
By : Kasden Hoffman
Quartz is probably the most common mineral. It is a compound of silicon, and oxygen, silicon dioxide. More commonly known as Silica. Quartz is important in many other rocks such as marble. Pure quartz is a colorless clear or white. But quartz can be gemstones if it has color to it. For instance, a purple quartz would just be a regular Amethyst.
Marble usually starts out as limestone compound, then it becomes marble because of heating from high temperatures from within the core of the earth which changes its mineral composition to make marbles beautiful coloring. Most marble is and can be used for tiling, counter tops, bathrooms etc.
Pumice is a type of volcanic rock. It is made when lava with a very high amount of water and gas is spewed out from the volcano. When this lava cools and hardens, this rock is a very light rock with tiny bubbles of gas inside. Pumice is the only rock that can float, even though it will eventually sink. Pumice floats because the tiny gas bubbles have a lower density than water and the tiny pockets of gas fill with water which make it float!
Sapphires are blue and violate in color, sometimes mistaken for a ruby for having a reddish color sometimes. The sapphire stands for sincerity, constancy, and truth. These beautiful gems are the birthstone for the people born in the month of September.
Ruby's are the birthstone for July. They stand for love, health, and wisdom. This gemstone is red ( hence the saying ruby red. )This gemstone has a lot of value to it, and the value increases based on the color and quality.
The Amethyst is said to represent strengthening relationships and a person who wears it has more courage. This is the most common and easily found gemstone and is the birthstone for the month of February. Amethyst is purple hued in color.
Aquamarines are a sky blue color and the birthstone for March. It gives youth, health, and hope. Aquamarine has an element of water given its cyan color. It is used in jewelry such as bracelets, necklaces, and rings. It is too a popular gemstone.
Limestone is a sedimentary rock that is made of calcium carbonate that is in the form of the mineral calcite. It forms in clear, warm, shallow marine waters. Most of the time it is an organic sedimentary rock that forms from a shell, coral, algal and fecal debris. It can also be a chemical sedimentary
Calcite is a common mineral and the only one that is non-silicate forming. Calcite has two refractive indices making a double refraction effect. When a clear calcite crystal is shown on an image, a double image is seen. Just look at the picture on the left! Did you know? : " Calcite will fizz when dilute hydrochloric acid is placed on it "
Basalt is dark in color, fine grained, and is igneous rock. It is made up of mostly of plagioclase and pyroxene minerals. It mostly forms as an extrusive rock like in lava flow.
Why are all Rocks, Minerals, and Gemstones not the same?
You may have heard the phrase 'rocks and minerals' at some point in your science schooling. The reason we say 'rocks and minerals' is because they are two different things. Rocks are not minerals, and minerals are not rocks.
A mineral is a solid, inorganic, naturally-formed substance that has a crystalline structure and specific chemical composition.First of all, minerals are solid and formed naturally in the earth. Natural solids can be familiar things like sand, granite, salt and wood. Our definition says that minerals are inorganic, which means that they do not consist of tissues from living things. So, that means that wood is not a mineral.
A rock is a solid, inorganic, naturally-formed substance without a particular atomic structure or chemical composition. It's probably easier to just remember that rocks are made up of two or more minerals. Examples of rocks include granite, limestone, marble, pumice, obsidian, sandstone, shale and slate. Each of these rocks consists of several different minerals, which are mixed up inside the rock through a variety of geologic processes.
Gemstones have their own science as well, called gemology, which is a branch of mineralogy. But the concept of a gemstone is based on human value judgements. A gemstone is usually defined as a highly attractive and valuable piece of cut and polished mineral that is used in jewelry or other decorations. The science of gemology studies the special physical and optical properties of this subset of the mineral world.