For sorting purposes, what is the maximum diameter for round gems suitable for sieves?

The maximum diameter for round gems suitable for sieves is 3mm. When sorting gemstones, especially small colored stones, sieves are utilized to separate them based on size. The choice of 3mm as the maximum diameter is significant because it allows for effective sorting without causing excessive clumping or loss through the sieve holes.

Gemstones that are smaller than this diameter can be sorted more efficiently, while those larger may not pass through the mesh and can lead to inaccuracies in sorting. Using a size of 3mm ensures that a wide variety of smaller stones can be processed quickly and effectively, which is crucial in both quality control and gemstone preparation processes. Additionally, using the correct size helps in achieving the desired classifications needed for further assessments or sales.

The other sizes are either too small or not optimal for general sorting and could result in either inefficient processing or complications in separating stones effectively. Therefore, recognizing 3mm as the upper limit helps in maintaining quality in sorting processes for colored gemstones.