@Percy
I don't really know since I never have a coin toned during the time I own it.
Most coins I bought are already slab except the silver $1 1971 ane above.
I read and hear that sulphur within the velvet, carton and cloth increase the oxidation.
That's why there are so many 1971/72/73 dollar nicely toned, all stored in the red velvet.
Same for 1967 set.
Also, many proof-like set (before the plastic oil was use) have deep toning because of the white carton holder.
See these 2 lots from TCNC auction.
I try to buy it but I was outbid.
https://auctions.canadiancoinsandpa...ion/87/lot/1
https://auctions.canadiancoinsandpa...ion/87/lot/2
We see the toning is stronger for the 10c and 25c because coins are smaller than 50c/$1 so toning cover the entire coin. Also, been less thickness there is more air coming in and interact with the carton.
I don't really know since I never have a coin toned during the time I own it.
Most coins I bought are already slab except the silver $1 1971 ane above.
I read and hear that sulphur within the velvet, carton and cloth increase the oxidation.
That's why there are so many 1971/72/73 dollar nicely toned, all stored in the red velvet.
Same for 1967 set.
Also, many proof-like set (before the plastic oil was use) have deep toning because of the white carton holder.
See these 2 lots from TCNC auction.
I try to buy it but I was outbid.
https://auctions.canadiancoinsandpa...ion/87/lot/1
https://auctions.canadiancoinsandpa...ion/87/lot/2
We see the toning is stronger for the 10c and 25c because coins are smaller than 50c/$1 so toning cover the entire coin. Also, been less thickness there is more air coming in and interact with the carton.






























