Can someone explain to me how toned coins can raise or lower the value of a coin. I just never understood it.
The same thing that dictates the price of any coin, eye appeal and the fact that it also makes for a unique coin. Its not for everyone and if a toned coin does not prompt you to spend a little extra then simply dont. I also think some people get caught up buying low graded toners with big premiums, its a hard market but if you are patient enough you can get some real bargains.
I wrote this thread over 4 years ago, it should be a good start to answering your question. Rainbow Toning's effect on price And this thread should provide you with many anecdotal examples. The Toning Premium Thread