quartz

	*`Morphology of etch pits in man-made and natural quartz crystals under hydrothermal conditions`*
	*`About the growth of the hexagonal prism of the crystals of a-quartz`*
	*`Hydrothermal growth of man-made corundum crystals`*
	*`Quartz`*
	*`Topaz`*

20.02.2004 г.