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.
Natural abundance. Silicon makes up 27.7% of the Earthâs crust by mass and is the second most abundant element (oxygen is the first). It does not occur uncombined in nature but occurs chiefly as the oxide (silica) and as silicates. The oxide includes sand, quartz, rock crystal, amethyst, agate, flint and opal. The silicate form includes asbestos, granite, hornblende, feldspar, clay and mica.