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Thanks, Nigel I really appreciate your comment Regards

It's sounds like they're all competing for the same listings "real estate". I would consolidate them onto the strongest domain and drive traffic to it that way. Are the sites in the same country? If you are targeting "local" you could create sub pages targeting that city.

If for some reason you need all the colors to have their own page (as opposed to putting all of the colors on one page, as Alick300 helpfully suggested) you can use rel=canonical links to choose one page to be the indexed one (the most popular color, perhaps).  If you are not familiar with canonicals, here is some information.