Seal Quartz Stone tiles?

[Big_Kev]

Hi, I've just laid a floor of Quartz Stone tiles in my bathroom. What I am wondering is whether I need to seal them? They have a sheen to them (they are shiny) with speckled bit's in, and when I have dropped water on or cleaned them, any moisture sits on top and does not soak in. I've not done the grout yet but thought it worth asking before I do!!

Thanks in advance!!