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.
in amphibole: Crystal structure. The fundamental building block of all silicate mineral structures is the silicon-oxygen tetrahedron (SiO 4) . It consists of a central silicon atom surrounded by four oxygen atoms in the shape of a tetrahedron.