The physical properties of the mineral from which the gem is cut determine its susceptibility to wear, breakage, and deterioration. Diamonds may be "forever", but other gems may not be, depending on their properties. cleavage plane ...
Author: DK
Publisher: Dorling Kindersley Ltd
ISBN: 1409341712
Category: Nature
Page: 224
View: 761
A gem is any mineral that is highly prized for its beauty, durability, and rarity. It is enhanced in some manner by altering its shape, usually by cutting and polishing. Most gems begin as crystals of minerals or as aggregates of ...
Author: DK
Publisher: Dorling Kindersley Ltd
ISBN: 1409364836
Category: Nature
Page: 352
View: 894
The Book of Beetles uncovers 600 significant examples, selected as part of a genome program. They are shown in glorious photographs, life size and in detail, alongside an engraving offering a side or open-winged view.
Author: Patrice Bouchard
Publisher: Ivy Press
ISBN: 1782402322
Category: Nature
Page: 656
View: 518
ROCK IDENTIFICATION ETC OUR OWN MAP GUIDES GOLD DIGGERS ATLAS ROBERT N JOHNSON NW GEM FIELDS & GHOST TOWN ATLAS ... TRAILS ABBOTT SEASHELLS OF NORTH AMERICA GOLDEN NATURE GUIDES FOSSILS SEAS INDIAN ARTS LAND FORMS Rocks & MINE - - - *.
Author: Humphrey Cyril Johnson
Publisher:
ISBN:
Category: Precious stones
Page: 79
View: 234