Material properties of diamond these are known as ballas and are important to industry as they lack the cleavage planes of single-crystal diamond. Carbonado is a similar opaque microcrystalline form which occurs in shapeless masses. Like ballas diamond, carbonado lacks cleavage planes and its specific gravity varies widely from 2.9 to 3.5. Bort diamonds, found in Brazil, Venezuela, and Guyana, are the most common type of industrial-grade diamond. They are also polycrystalline and often poorly crystallized; they are translucent and cleave easily. Because of its great hardness and strong molecular bonding, a cut diamond's facets and facet edges appear the flattest and sharpest. A
What Is Life what he needs from his old band – that insinuating hook sense – and uses it to frame an utterly comfortable metaphysical discourse". Alan Clayson describes "What Is Life" as a seemingly "lovey-dovey pop song" that "craftily renewed the simplistic tonic-to-dominant riff cliché", while Simon Leng credits Harrison's "innate ability to write very fine pop-rock songs" and deems the result "as innovative an exercise in rock-soul as The Temptations' 'Cloud Nine'". Among Harrison biographers, only Ian Inglis is less than enthusiastic, acknowledging that Barham's orchestration and the other musicians give the track "undoubted excitement and energy", but lamenting that the