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How Before the Slab Works

Events, grade markets, practice $JKB, the Collector Market, filled vs resting predictions, market depth, and PSA-result settlement — explained collector-first.

Updated 2026-07-02

On this page

Before the Slab is easiest to understand as a grading window with memory. The card is not back yet. The market still has an opinion.

This page explains the machinery in collector terms: what an event is, what practice $JKB is, how the Collector Market matches predictions, and how the final PSA result settles everything. Everything here uses practice $JKB — simulated, with no cash value.

The short version

A raw card goes out for grading. Before the slab comes back, collectors make practice predictions about the grade — PSA 10, PSA 9, and so on — using practice $JKB. Predictions from different collectors meet in the Collector Market: some match immediately, some wait for another collector to take the other side. When the official PSA result arrives, it settles the practice market and the event keeps a record of what collectors believed before the result existed.

One event, start to finish — the final PSA result is the referee.

Events and grade markets

An event is one card being followed before the slab comes back. Each event defines its possible outcomes, and each outcome gets its own grade market.

The grade markets are independent: the PSA 10 market and the PSA 9 market each have their own prices and their own collector interest. Exactly one outcome ends up correct when the result arrives.

Each grade market prices its outcome separately — exactly one settles YES.
  • Event = one card in its grading window, with owner-approved evidence photos.
  • Grade market = one possible outcome for that event (for example PSA 10, PSA 9, PSA 8 or lower, or No Numeric Grade).
  • Each grade market prices its outcome separately — collectors weigh centering, corners, surface, and eye appeal per outcome.

Practice $JKB

Practice $JKB is the simulated balance used for practice predictions. It has no cash value, cannot be bought, cannot be withdrawn, and cannot be converted into anything. It exists so collectors can back a read with something at stake in the game sense — reputation and bragging rights — without any real money anywhere in the loop.

New collectors claim a starter amount of practice $JKB after verifying their email. Verified email is the participation gate for making predictions.

The Collector Market

The Collector Market is where practice predictions meet. When you make a prediction, you are choosing a side of a grade market at a price, and the market looks for another collector willing to take the other side.

Before the Slab uses an internal CLOB-style matching engine behind the scenes, but the user-facing experience is simple: collectors make practice predictions, those predictions can fill immediately or rest in the Collector Market, and the final PSA result settles the practice market.

This is internal practice-market infrastructure. Practice $JKB has no cash value, and Before the Slab is not a financial product.

YES and NO reads

Every grade market has two sides. YES means you think that outcome happens — the card really does come back PSA 10. NO means you think it does not.

Prices are shown per share in practice cents. A YES price of 60¢ means the market currently leans toward that outcome; the matching NO side of the same market prices the other way. YES is always shown in green and NO in red across the product.

Buy offers, sell offers, and market depth

At any moment a grade market holds two lists: buy offers (collectors willing to buy a side at a given price) and sell offers (collectors willing to sell at a given price). The best of each side is summarized as the top buy, the top sell, and the gap between them.

Market depth is how much collector interest is available at different prices. A deep market can absorb larger predictions without the price moving much; a thin market moves faster. The Market depth view on an event page shows those offers directly.

Depth is how much collector interest waits at each price — all in practice $JKB.

Filled vs resting predictions

Filled means your prediction matched right away — another collector was already offering the other side at your price, so your shares are yours immediately.

Resting means your prediction is waiting in the Collector Market for another collector to match it. Nothing is lost while it rests: the practice $JKB it would use is set aside, and you can cancel a resting prediction any time before it fills.

Predictions can also fill partially — some shares match now and the rest either rests or is returned, depending on the option you chose when submitting.

Partial fills are both at once: some shares fill now, the rest rests or returns.

Why prices move

Prices move because collectors trade. When more collectors want YES on a grade than are willing to sell it, matches happen at higher prices and the displayed price rises. When conviction fades, it falls.

Nobody sets the price by hand — it is simply the most recent place where two collectors agreed. That is why the price chart reads as a record of shifting collector conviction across the grading window.

How settlement works

When the official PSA result comes back, the event resolves. The grade market matching the real result settles as YES; every other grade market settles as NO.

Shares on the correct outcome settle at full practice value; shares on the other outcomes settle at zero. Practice balances update, the event page shows the stored result, and the market record — who read the card right before the slab came back — remains.

Settlement is based on the final documented PSA result for that specific card. JK Index publishes the resolution on the event page.

Practice balances update and the event keeps the record of who read it right.

No numeric grade and other edge cases

Sometimes a card comes back without a numeric grade. That is why events can include a No Numeric Grade outcome — it is a real possibility collectors can price like any other.

If an event cannot be resolved cleanly — for example the card never receives a documented result — the event follows its stated resolution rules, and practice balances are handled accordingly. Every event page states its outcomes and timeline up front.

What this is not

There is no real money anywhere in Before the Slab. Practice $JKB has no cash value and no path to cash value — nothing converts, nothing withdraws, nothing pays anyone.

Before the Slab is not a financial product, not investment advice, and not on-chain today. It is not a grading service: JK Index does not grade the card and does not influence the result.

JK Index is not affiliated with PSA or any other grading company and does not claim official endorsement or partnership. PSA results are simply the documented outcome that settles the practice market.

Quick glossary

  • Event — one card being followed before the slab comes back.
  • Grade market — one possible outcome for that event.
  • YES — you think that outcome happens.
  • NO — you think that outcome does not happen.
  • Practice $JKB — simulated balance used for practice predictions; no cash value.
  • Filled — your prediction matched right away.
  • Resting — your prediction is waiting for another collector to match it.
  • Market depth — how much collector interest is available at different prices.
  • Settlement — the final PSA result decides which outcome was right.

Next steps

Now that you understand the mechanics, here are the best places to go next.

Before the Slab overviewThe idea behind the product and why it exists.Why this market existsThe collector market problem in plain terms.Start exploring Before the SlabSee live practice events in the product.