Can barium sulfate be prepared by precipitation?

Yes, barium sulfate can indeed be prepared by precipitation. This process involves mixing a soluble barium salt (such as barium chloride or barium nitrate) with a soluble sulfate salt (such as sodium sulfate or ammonium sulfate) in a solution. 

When these two solutions are combined, insoluble barium sulfate precipitates out of the solution as a solid. This solid can then be collected by filtration and washed to remove any impurities, resulting in pure barium sulfate. 

This precipitation reaction is often used in analytical chemistry for the qualitative and quantitative determination of sulfate ions in solution.