What is uncoated swarovski crystal?

I'm planning on buying some swarovski crystals for card making and some sites are offering uncoated crystals. What is uncoated? is it less sparkly or is it just a cheaper version?|||The uncoated ones do not have the multi-colored sheen that some of the crystals give off, they are just the true color|||I think they mean that they didn't put another color over it.