Ultramafic rock but there are ultrapotassic and highly silica-under-saturated rocks with >18% MgO which can be considered "ultramafic". Ultrapotassic, ultramafic igneous rocks such as lamprophyre, lamproite and kimberlite are known to have reached the surface of the Earth. Although no modern eruptions have been observed, analogues are preserved. Most of these rocks occur as dikes, diatremes, lopoliths or laccoliths, and very rarely, intrusions. Most kimberlite and lamproite occurrences occur as volcanic and subvolcanic diatremes and maars; lavas are virtually unknown. Vents of Proterozoic lamproite (Argyle diamond mine), and Cenozoic lamproite (Gaussberg, Antarctica) are known, as are vents of Devonian lamprophyre (Scotland). Kimberlite
Gemstone (database) of VMware, announced it had entered into a definitive agreement to acquire GemStone. On May 2, 2013, GemTalk Systems acquired the GemStone/S platform from Pivotal Software (the EMC and VMware spin-off).. Gemfire remained with Pivotal's Big Data division. The product is available standalone but is also integrated into its Cloud Foundry PaaS as "Pivotal Cloud Cache". GemStone builds on the programming language Smalltalk. GemStone systems serve as mission-critical applications. GemStone frameworks still see some interest for web services and service-oriented architectures. A recent revival of interest in Smalltalk has occurred as a result of its use to generate JavaScript for