is a plagioclase feldspar that shows a distinct adularescence or shiller ,due to numerous hematite plates that reflect light in various directions.
The classic sunstone,well known in the market comes from India and is generally cut in a cabochon shape in order to appreciate the shiller effect. The orientation of the table is very important in order to get the maximum result of light reflection. Normally the size of these stones are small ,because the rough material has many fractures and considering the orientation of the stones there is a low yeld of good material.Even though small fractures are accepted.Therefore a stone over 10 ct with a minimum cracks is considered a nice good quality stone. From India.