That article is worthless in regards to the UHR. It is discussing copper spots on 90% coinage gold which are to be expected on the classic coins. UHRs are 24KT .9999 pure gold so 1 part in 10,000 should not cause spots. I guarantee that a spot on a UHR(or any 24KT billion) will lower the grade.
Disclaimer: While a tremendous amount of effort goes into ensuring the accuracy of the information contained in this site, Coin Community assumes no liability for errors. Copyright 2005 - 2026 Coin Community Family- all rights reserved worldwide. Use of any images or content on this website without prior written permission of Coin Community or the original lender is strictly prohibited. Contact Us | Advertise Here | Privacy Policy / Terms of Use