Grading Proof 70 modern commemoratives

[Dave Stone-migration]

I have a number of PR70 modern commemorative coins from both NGC and other grading services. Some of the older coins have some toning on them and my question is this: at what point does the toning cause the coin to be officially downgraded? Also, if a PR70 coin from another grading service is submitted for CrossOver service, will the coin not received a PR70 designation based solely on the presence of a small amount of toning?

[Jay Turner]

It is very common for proof coins, due to their delicate surfaces, to acquire haze over time and it does factor into the grade. How much of a factor depends on how thick the haze is and/or how disruptive the haze is over the mirrored surfaces.

 

For cross over often coins with this haze or toning will be rejected for the grade of 70 because hairlines may be hiding under the haze.

 

Often conservation thru NCS will be able to remove the haze, allowing the coin to maintain the 70 grade or allowing the coin to grade 70 when before the coin was being hindered.

 

Jay Turner

NGC Grader and Attributor

[regandon-migration]

Mr. Turner,

 

Once a proof coin is in a slab, will the coin still haze ? I have some proof 69 coins that have a nice gold toning on them, again, if the coin is slabed, will the toning stop ?

 

Don

[WaxonWaxov]

haze mostly happens due to humidity and/or oxygen right?

[CHRISS]

The hermetically sealed NGC holders will prevent future hazing to occur. Once in an NGC holder, any contaminants on the surface of the coin will not be able to interact with the air and humidity to create further residues or toning. A third major factor in a coin's hazing or toning--temperature--can still be a factor with a hermetically sealed holder. Store your certified coins in as constant a room temperature location as possible.

 

The haze on modern proof coins is typically due to environmental factors such as the humidity and air and temperature interacting with chemicals in the coin's holders. Original proof set holders, for example are not air tight and residues can form on the coins inside due to humidity and chemicals in the air interacting over time. PVC residue can leave a haze on modern proof coins through interactions of heat and humidity with the chemical inside the soft plastic flips.

 

Professional conservation such as that offered by NCS can often remove hazing issues before a coin is to be certified by NGC. Contact NCS Customer Service for additional information on this service at 866-627-2646 or NCShelp@NCScoin.com.

 

Chris, NCS