Pebeo Artist Acrylics Crystal Mortar - 250 ML is a transparent, granular, matt finish mortar made from a mixture of acrylic polymer and quartz crystals. It achieves the effects of transparent and granular materials that reflect light. It can be used alone or tinted with colours. When mixing with this mortar, it is preferable to use transparent colours. It is thicker and heavier than other mortars and can be mixed with Bindex to improve its adherence to the painting surface.