Fluorescent gypsum satin spar mineral specimens from Morocco, which are a pearly white colour composed of high quality fibrous crystals which are long and orientated in the same direction giving the samples a silky lustre. Satin spar is a variety of gypsum which is well known by many, it has a pearly white colouration, a fibrous crystal habit and a silky lustre. As expected, it is an evaporite mineral and has been found on all continents of the world. It forms when fluids which contain the mineral (diluted) evaporate leaving the mineral behind to grow and can be found in salt flats, lakes, evaporated seas, caves and more. It is a common mineral and highly sought after for mineral collectors, educational bodies and in industry where it's main use is in the manufacture of plaster of Paris. Samples fluoresce a pale blue to purple colour when under shortwave UV light. These pieces are supplied in a 2" x 2" card tray with a label. Ideal for collectors of fluorescent minerals.