Common, coarse-grained variety of quartz that ranges in colour from nearly black through smoky brown. No distinct boundary exists between smoky and colourless quartz. Its abundance causes it to be worth considerably less than either amethyst or citrine. Heating bleaches the stone, the colour sometimes passing through yellow; these yellow pieces are often sold as citrine.
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Where do the Cairngorms begin? Four years after it was created, a debate is raging over how big the national park should be, writes David Ross
Feb 06, 2007; ITis nearly four years since the cairngorm National Park came into being, but motorists on the A9 are still not officially...