Mineral site, and from there further subdivided by the chemistry of the W site. The Y and Z sites can accommodate a variety of cations, especially various transition metals; this variability in structural transition metal content gives the tourmaline group greater variability in colour. Other cyclosilicates include beryl, AlBeSiO, whose varieties include the gemstones emerald (green) and aquamarine (bluish). Cordierite is structurally similar to beryl, and is a common metamorphic mineral. Sorosilicates, also termed disilicates, have tetrahedron-tetrahedron bonding at one oxygen, which results in a 2:7 ratio of silicon to oxygen. The resultant common structural element is the [SiO] group. The
Zoysia 'Emerald' Zoysia 'Emerald' Emerald Zoysia ("Zoysia" 'Emerald') is a cultivar of "Zoysia" grass with a thin bladed leaf that forms a very lush lawn. It shares the drought and shade resistance of the other varieties. This grass has a fine, soft texture and can be left unmowed as it only grows to a height of . When left unmowed, it forms a humpy convoluted surface which is sometimes used in oriental landscapes (see picture on Zoysia page). Emerald Zoysia is adapted to zones 7-11 and does well in warm, humid environments. It is an excellent grass for the southern and southeastern