Conclusion: Meticulous preservation and professional grading are consistently observed to be critical for maintaining the pristine condition
NGC, PCGS Grades Can Plummet Without Proper Coin Storage
Mar 31, 2026CoinTalk
Risk & Authentication
Environmental Damage
Corrosion, pitting from burial or exposure
3 articles
Action: Extract uncirculated silver coins from deteriorating acrylic blocks immediately; acid off-gassing causes 2+ grade deterioration—extraction cost now justified by preservation.
Lucite Blocks Threaten 1964 Silver Coins, NGC Regrading Urged
Mar 29, 2026CoinTalk
Conclusion: A significant collection of NGC-authenticated Seated Liberty half dollars from the S.S
NGC-Graded Seated Half Dollars from the S.S. Republic Shipwreck Head to Auction
Mar 1, 2026CoinTalk