1. Collect the bronze pearl pigment mixed with impurities in a container.
2. Take a fine mesh strainer or sieve with a mesh size that is smaller than the particle size of the pigment. Select a sieve size that will allow the pigment to pass through but will catch any large impurities.
3. Place the strainer or sieve over a clean container.
4. Pour the bronze pearl pigment mixed with impurities into the strainer or sieve.
5. Using a spatula or spoon, gently press the mixture through the strainer or sieve, being careful not to force any large impurities through the mesh.
6. Continue to press and stir the mixture until all of the pigment has passed through the mesh, and only impurities remain in the strainer.
7. Collect the screened bronze pearl pigment in the clean container beneath the strainer.
8. Repeat the process two or three times, if necessary, to ensure that all impurities have been removed.
9. Dispose of the impurities in the strainer appropriately.
10. Store the purified bronze pearl pigment in a clean, airtight container until ready to use.