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) web application server platform. (VisualWave and VisualWorks are now owned by Cincom.) GemStone played an important sponsorship role in the Smalltalk Industry Council at the time when IBM was backing VisualAge Smalltalk, now owned by Instantiations, Inc. After a major transition, GemStone for Smalltalk continued as "GemStone/S" and various C++ and Java products for scalable, multitier architecture distributed computing systems evolved into the "GemStone/J" product. This in turn gave rise to "GemFire", an early example of a Data Fabric for complex event processing (CEP), event stream processing (ESP), data virtualization, and distributed caching. On May 6, 2010, SpringSource, a division