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 Publishing Suspenstories" Vol. 1 and "Tales From the Crypt" Vol. 1 have been published. In early 2009, the future of Gemstone Publishing was unclear, after reports of unpaid printing bills, particularly from the EC Archives. In April, Geppi responded to the uncertainty, noting that while there had been "a reduction in staff at Gemstone," such moves did "not [signal] the end of Gemstone Publishing." Seven months after Geppi's optimistic statements, the last batch of Gemstone's Disney comics appeared in November 2008, complete with previews for next month's issues that Gemstone was to fail publishing. BOOM! Kids acquired all comic publishing licenses