If a coin is toning is that good or bad will it make the price go up or down and will the toning hurt the grade
Good or bad is a matter of opinion, if its real attractive market acceptable toning it will bring a premium and no it wont affect the grade. Its also important to remember the quality of the coin will have a big impact on the price. You really should do some reading on toned coins if deciding to collect them, it can be alot of fun and i personally enjoy a nice toned coin...
Sadly, the answer of "yes" is pretty spot on to this question. (Natural) Toning is the result of a non-controlled chemical reaction. As such, you can end up with what some collectors consider beautiful toning (rainbows, saturated hues) or, more commonly, black/brown coins. The demand for such coins would be based upon the market that you're selling to. Some collectors prefer blast white coins (since you can fully see the surfaces and get a true grade), while others prefer the aged look and unique patterns that toning can provide. Essentially, this demand will determine the price. As for the grade being hurt, it's not _supposed to_, but it might. This is in the case of the brown/black toning that I mentioned earlier. If a coin is severely toned in an undesirable shade/color, the grading would be impaired. This is due to the "eye appeal" aspect of a coin's grade. Technically, a coin might grade at a certain level (say MS64), but it's toning might be completely awful and destroy the eye appeal significantly enough to bring that grade down (say to MS62).
IMO, toning and anything else that comprises "eye appeal" is based on collectors' tastes which is subject to change. Things that fascinate collectors today may not fascinate them tomorrow. Or may not fascinate them as much tomorrow. That's the whole paradox of eye-appeal and market grading-it's very real, but at the whims of very whimsical coin collectors.
