bead problem

[T.G]

Is he sure it's mold?

If he's adding water to the beads by pouring or squiting it on them it could be a few beads shattering into a powder and he's seeing the powder forming a crystaline structure (I've seen this with my beads).

If he's not using distilled or deionized water, then he could be looking at impuritues plating out from the water.