I guess its best for me to stay away from buying toned cents. These to me look artificial! I would beleive you if you said they were natural, but I just don't have the eye for it.
The link below is the thread about the hoard that I bought last year. I don't know whether these were intentionally toned this way or if the toning was caused by how the coins were stored. My dealer had purchased pails full of coins from an old time collector about 25 years ago and they had sat in his garage since then until I purchased them. http://www.cointalk.com/t83989/
I sold the majority of the bulk to a collector who wants to put together sets for his kids. I kept some of the BU rolls and most of the "collectible" coins (eg. errors, varieties, etc.). I managed to re-coupe my initial investments and put together a pretty nice collection. The new buyer will still find a lot of decent coins because I left a lot of the duplicate varieties in what he bought. He also bought a portion of my wheats from another hoard which covered that investment as well.
There is a huge difference with the first cent you pictured and the canadian cent simms showed. The layout and "intermingle" between colors are one way of telling. Now in order to have an idea on how to detect AT from NT coins is a matter of experience in collecting, research, and learning from more experienced collectors with the same interest.
Sage advice! I keep ALL of my toners in airtites to halt the toning. Given enough time and exposure to air they tend to become ugly.
Some pennies I got roll hunting \ I like the 65' alot, I don't find many like this in the 60's roll hunting.
I recently received this 1954 proof cent back from PCGS grading. Apparently PCGS still grades some colorfully toned copper. I have posted this on their boards as well as NGC's. If you've seen it previously, I apologize for making you look at it once again.
I just opened a yellow envelope from the bottom of my childhood coin-collection box. It was apparently a pouch of five BU Lincoln cents; I guess I would've bought it 35 or 40 years ago. I'll have to post some pics of what I found -- let's just say that there are lots of rainbow tones, but I don't think anybody's going to be bidding them up.
This was a great thread to revive. I loved reading about Greg's quest for toners and education in that field. Now look at him, the master of the toned coin! ETA: and coin photograpy!