I think nickel 586's are rarer then blue ones by a wide margin but maybe not as low as only 10% of those made. At gun shows in local gun shops I have seen only one for sale with a 6 inch barrel and I've seen lots of blued 586's for sale. I also think it doesn't matter hold rare a nickel gun might be because if it's not new and unfired in the box with all the goodies it's not worth more then a blued gun that's been fired.