1. In geology, a fine - grained volcanic rock composed of alkali feldspars and nepheline. 9 letters 2. Unglazed, typically brownish-red earthenware used chiefly as an ornamental building material and in modelling. 10 letters 3. A magical or medicinal potion. 6 letters 4. An alloy of gold with at least 20% of silver, used for jewellery. 8 letters