is mercury gray or a orange?

neither
It is metalic. I guess grey is by far the closest though.

I think it's silver!!!

Are you talking about the metal or the planet?

Since neither is not my area of expertise, I searched Google under the key words "mercury color" to get these possible sources:

http://coolcosmos.ipac.caltech.edu/cosmic_kids/AskKids/mercury_color.shtml
http://72.14.253.104/search?q=cache:H0_jpHtXieYJ:www.lpi.usra.edu/meetings/lpsc97/pdf/1689.PDF+mercury+color&hl=en&gl=us&ct=clnk&cd=2&client=safari
http://www.chemicalelements.com/elements/hg.html
http://encarta.msn.com/encyclopedia_761556180/Mercury_(element).html

I hope this helps a little more. Thanks for asking.

what is the physical features of mercury??