Store in safety containers and do not use near open flames or cigarettes. Do not use plaster for body part casts. It can be painted with paint or powdered pigments, or dyes can be added directly to the plaster mix. Patinas are made by sealing the plaster with shellac or acrylic sprays. Powdered pigments and dyes are often hazardous by inhalation or ingestion, and in some cases by skin contact.
Lacquers contain solvents that are highly toxic by inhalation and moderately toxic by skin contact.
Alcohol and shellac are slightly toxic unless the shellac contains moderately toxic methyl alcohol. These solvents are also flammable. Brush or dip dyes or paints rather than spraying. When using solvents, have good general ventilation and wear gloves and goggles. Soft stones can be worked with manual tools whereas hard stones require crushing and pulverizing with electric and pneumatic tools.