What is a slab?
A slab is the sealed plastic holder a grading company encapsulates a coin in after evaluating it. It carries a label with the cert number, the grade (Sheldon 1–70) and the piece data. Once sealed, the coin can't be handled without breaking the holder.
Graders recognised on GSG
- PCGS (Professional Coin Grading Service) — reference for modern and US.
- NGC (Numismatic Guaranty Company) — international reference.
- ANACS — historic US grader, accepted but less premium.
- ICG — independent grader with solid worldwide coverage.
Any of the four is valid. Choice doesn't change GSG fees.
How to add it when listing
Go to New listing. In the "Certification" section:
- Toggle "Certified piece".
- Pick the grader (PCGS / NGC / ANACS / ICG).
- Enter the cert number (visible on the slab label).
- Enter the grade (e.g. MS-65, PR-69, AU-58).
- Upload a photo of the full slab with a readable label.
What the buyer sees
On the product page:
- "Certified [Grader]" badge next to the title.
- Grade highlighted.
- Cert number clickable (links to the grader's public database when available).
- Holder photo in the gallery.
When certifying pays off
- ✅ High-value pieces (≥€5,000.00): the premium serious buyers pay easily covers the slabbing cost.
- ✅ Borderline-grade pieces (MS-63 vs MS-65 can multiply price).
- ✅ Rare or ancient numismatics where authenticity is half the value.
When NOT to certify
- ❌ Standard bullion (current-year Maple Leaf, American Eagle) — the slab doesn't beat weight/purity.
- ❌ Low-value pieces where the slab cost won't be recovered.
- ❌ If you plan to keep the piece "raw" — slabbing is effectively irreversible.