This video lecture from Group IIIA and Group IVA Elements (F.Sc. second year Chemistry) covers the various varieties of quartz crystals. Quartz are classified as rock crystal which is colorless, citrine which is yellow to brown in color, rose quartz which is pink to red in color, amethyst which is purple in color, smoky quartz which are gray and milky quartz which shows white color. Find more e-learning material and educational video lectures in Urdu at maktab.pk. These videos are free to use for promotional and commercial purpose by keeping the credits to Maktab.