lustre

views updated May 08 2018

lustre Of minerals, the ability to reflect light. The quality and nature of the reflection may be a useful diagnostic aid. The term ‘lustre’ is often used in conjunction with the qualifying terms ‘adamantine’, ‘metallic’, ‘resinous’, ‘waxy’, ‘pearly’, ‘silky’, ‘greasy’, and ‘vitreous’. The intensity of the reflection is qualified by descriptions such as ‘shiny’, ‘dull’ or ‘splendent’.

lustre

views updated May 29 2018

lustre2 sheen, gloss; luminosity, brilliance. XVI. — F. — It. lustro, f. lustrare :- L. lūstrāre light up :- *lūcstrāre, f. lūx, lūc- LIGHT1.
Hence lustrous XVII.

lustre

views updated May 29 2018

lustre1 period of five years. XIV. — L. lūstrum, prop. quinquennial purification, of uncert. orig.
So more usual lustrum XVI. lustration expiatory sacrifice, etc., purification. XVII.