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
Gemstone (database) e-commerce web pages or in web application frameworks such as the Seaside web framework. Systems based on object databases are not as common as those based on ORM or object-relational mapping frameworks such as TopLink or Hibernate. In the application framework market, JBoss and BEA Weblogic are somewhat analogous to GemStone. Gemstone (database) GemStone/S is computer software, an application framework that was first available for the programming language Smalltalk as an object database. It is proprietary commercial software. GemStone Systems was founded on March 1, 1982 as Servio Logic, to build a database machine based on a set theory model.