What is a slab in comic collecting?
Published Sep 14, 2026 · Updated Sep 14, 2026 · 1 min read
Short answer“Slab” is collectors' slang for the sealed plastic holder a grading company such as CGC or CBCS puts a comic in after grading, and by extension for the graded comic itself. A slabbed comic has a label with its grade and certification number and cannot be read without breaking the case. The term comes from the coin-collecting hobby, where encapsulated coins were called slabs first.
What a slab is
The holder has three parts: a rigid outer case, an inner well that holds the comic without pressure on the spine, and the label sealed in at the top. The seam is ultrasonically welded so the case cannot be opened without visible damage. Older CGC holders and the current design differ slightly in shape; both are archival and inert.
Slabbed vs raw
A slabbed book has a third-party grade you can verify; a raw book has whatever the seller says. The trade-off is that a slabbed book cannot be read, costs more, and needs more space and heavier packaging. See What is a raw comic? and Should I get my comic graded?.
Terms you will hear
- Cracking a slab — opening the case, usually to press and resubmit the book or to read it.
- Reholder — sending a slab back to the grader for a new case when the old one is scratched or cracked; the grade is unchanged.
- Crossover — submitting a book graded by one company to another, keeping the grade only if it meets a minimum you set.
- Newton rings — the rainbow patterns sometimes visible where the well touches the cover; cosmetic only. See What are Newton rings?.
Handling and storage
A slab protects the book from handling but not from heat, humidity or sunlight. Store slabs upright or flat in a cool, dark place and ship them in a box with padding on all sides — see How to ship a graded comic.
Written by the Rare Comics Collectors grading team. Spotted an error or have a question this guide does not answer? Tell us.