My friend recently purchased a table (that I know originally is from overseas somewhere)?

Lately there's been a random area of a fine powder in the middle of the table. It's in the center and always in the same exact spot, in a contained area. It seems to happen over night, usually she'll clean it off in the evening when she gets home. I know the table is made out of grass oak and lately there's been about a quarter thick crack developing on the table of the table (on top and bottom). It doesn't seem to be coming from the ceiling, and there's nothing on the chandelier or the plants that she has on the table. Has anyone ever heard of this? Could it be some kind of bug effect? It sounds bizarre, so i'm hoping someone can help. Thanks!