Can I mix particles w/ wax when I make candles without having them settle down?

I want to make a candle and I need to put small particles inside it. For example I want to put sand evenly inside the candle. Do you think I can just mix it with molten wax without worrying that the particles will settle down. Or what do you think should be done. I am expecting to have ground shells (mussel or oyster..im not yet sure) so please consider particles like small flakes, heavier and larger than sand particles. Thanks!