For U.S. Treasuries traded with a Fidelity representative, $19.95 per trade. Fixed income trading requires a Fidelity brokerage account with a minimum opening balance of $2,500. Rates are for U.S. Dollar denominated bonds, additional fees and minimums apply for non-Dollar bond trades.
A group of minerals containing various amounts of the elements Silicon and Oxygen. The Silicates are the largest group of minerals. The construction component of all Silicates is the tetrahedron, which is one Silicon atom equidimensionally placed around four Oxygen atoms.
Silicon is a metalloid, one of only a very few elements that have characteristics of both metals and non-metals. Silicon is the second most abundant element in the Earth's crust, exceeded only by oxygen. Many rocks and minerals contain silicon.Examples include sand, quartz, clays, flint, amethyst, opal, mica, feldspar, garnet, tourmaline, asbestos, talc, zircon, emerald, and aquamarine.Silicon never occurs as a free element.ilicon never occurs as a free element in nature. It always occurs as a compound with oxygen, magnesium, calcium, phosphorus, or other elements. The most common minerals are those that contain silicon dioxide in one form or another.