Initially, it may seem extremely daunting to be sitting in front of several thousand carats of
small diamonds, knowing that the likelihood of finding a diamond with a meaningful …

A definition for ultrapotassic rocks is introduced using the chemical screens K 2 O> 3 wt.%,
MgO> 3 wt.% and K 2 O/Na 2 O> 2 for whole-rock analyses. On this basis a data base of …

Crustal recycling at convergent plate boundaries is essential to mantle heterogeneity.
However, crustal signatures in the mantle source of basaltic rocks above subduction zones …

Trace-element data for mid-ocean ridge basalts (MORBs) and ocean island basalts (OIB)
are used to formulate chemical systematics for oceanic basalts. The data suggest that the …

Data from experimental runs, coexisting phases in ultramafic rocks and phenocryst-matrix
pairs in volcanic rocks have been used to compile a table of mineral-liquid distribution …

Exchange between a magma ocean and vapor produced Earth's earliest atmosphere. Its
speciation depends on the oxygen fugacity (f O2) set by the Fe3+/Fe2+ ratio of the magma …

In 1794, the German physicist EFF Chladni published a small book in which he proposed
the extraterrestrial origin of meteorites. The response was skepticism and disbelief. In the …

Peridotite xenoliths from the Olmani cinder cone, northern Tanzania, possess distinctive
mineralogical and chemical features interpreted to result from interaction of ultra-refractory …

A model is developed for the origin of ultrapotassic melts by melting of veined lithosphere;
the veins are rich in clinopyroxene and mica, whereas the wall-rocks consist principally of …

Major and trace element data for 375 spinel lherzolite and harzburgite xenoliths from
continental basalts are used to constrain the nature and composition of the continental …