GEMSTONES have been the prized possession of man and have constituted an essential material for his personal adornment for countless ages. They are the essentials of good jewellery - the result of fine workmanship and individual skill. Apart from various chalcedonic forms of silica and some lesser known stones used in the production of baroque jewelry, opal is the only gem stone being produced commercially in South Australia. This State however, supplies some 90% or more of the world's market for precious opal. A few other gemstones occur at scattered localities but in neither sufficient quantity nor quality to warrant commercial exploitation. Some top quality tourmaline and high grade malachite have been mined in the past but the deposits are now apparently exhausted. This collated series of Mineral Information Series brochures are for the years 1960 and 1970