The Practical Study of Minerals .
How to identify minerals using techniques based on both physical (crystallographic, twinning, cleavage, hardness, density, streak, colour, lustre, acid reaction, taste etc) and optical properties under the petrological microscope (relief, pleochroism, birefringence, extinction etc) Monday 29th April, for 10 weeks, until 15th July (not 6th nor 27th May). Held at Wynstones School, Stroud Rd, Whaddon, Gloucester from 7.30-9.30pm on Mondays. Cost £75.