Alternatively, my other design was:

­: Put a peach counter on ~.

­, Remove a peach counter on ~: Add one mana of any color to your mana pool.

But I was concerned about the powerlevel and I'm not a fan of counters on lands at uncommon, so here this is. A much better version of the Kamigawa dual lands. A bit concerned about eternal format power level, but I don't think this is that much better in those formats than, say, Gemstone Mine or Mana Confluence.

Other design is just a Mirrodin's Core -- or an awful version thereof, if you intended to have not T:C.

--CF

This seems an interesting comparison to Tendo Ice Bridge. Power level doesn't seem obviously too high or too low.