[1 Lucky Texan]

I dunno about Royal Purple, but Redline LightWeight Shockproof (and the other weights I guess) very purposefully has particles suspended in it. They are part of the technology used for lubrication/protection of gear surfaces. In fact, they explain the product should never be used in an application that has a pump/filter.

Anything floating in the fluid where the magnets are clean is either aluminum or rubber/seal material or some other non-ferrous 'slime'/carbon.