Collections

Every slab is one atom

A slab is matched to its exact printing, grader and grade, and takes that atom's published fair value. Two copies of the same card count twice. A slab never sold at its grade carries a reviewed estimate, marked as one, until a fair value replaces it.

A constant basket

The history line sums the same slabs on every day it shows, starting on the first day all of them had a value. A card gaining its first value moves the total and the count, never the line.

Two ways to read it

Value is the plain sum in dollars. Performance rebases every slab to 100 and averages them, so the line shows how the collection moved rather than how its single largest card did.