Conservation vs Cleaning
Cleaning is aggressive removal of surface material — acids, abrasives, or mechanical action that damages the coin. It's destructive and irreversible.
Conservation is careful, targeted treatment to remove harmful contaminants (PVC, verdigris, environmental deposits) while preserving the coin's original surface. It's performed by trained professionals using techniques and chemicals that don't damage the metal.
What Conservation Services Do
- Remove PVC residue from soft flip contamination.
- Stabilize or remove active verdigris (green corrosion on copper).
- Remove light environmental deposits or haze.
- Stabilize surfaces to prevent further deterioration.
Conservation Providers
- NCS (NGC Conservation Services) — NGC's in-house conservation arm. Coins can be submitted for conservation before grading. Fee: $25–$50 per coin plus grading fees.
- PCGS Restoration — PCGS offers restoration services. Fee: $25–$50 per coin.
When Conservation Makes Sense
- A valuable coin with PVC contamination that would otherwise receive a Details grade.
- A coin with active corrosion that will worsen without treatment.
- When the cost of conservation + grading is justified by the improved grade and value.
Up Next
This guide is for educational purposes. Where official standards, grading services, organization memberships, or legal requirements apply, consult the primary authority named in the references below or the relevant government agency.
Reviewed on January 24, 2026 by the US Coin Shows editorial team. Editorial policy
Frequently Asked Questions
What is the difference between cleaning and conservation?
Cleaning aggressively removes surface material and is destructive. Conservation carefully removes harmful contaminants (PVC, verdigris) while preserving original surfaces, performed by trained professionals.
How much does coin conservation cost?
NCS (NGC) and PCGS restoration charge $25–$50 per coin plus grading fees. It makes sense when the improved grade and value justify the cost.
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