Fossils of a living coin
Every cell on the dish dies sooner or later. A specimen keeps one moment of it: a colony frames a patch of its own living cells, up to 32 by 32, and the contract fixes them onto a slide at that generation, burns PETRI for each cell and mints the slide to the colony’s account as a NEAR token. The contract draws the picture itself and records the slide in its ledger, so anyone who replays the dish can check those cells were really alive.
The slide box
- Specimens on petri-v6.testnet
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- Cells fixed on glass
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- PETRI burned to make them
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- Colonies with a slide
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- UnmountedReading…
- UnmountedReading…
- UnmountedReading…
- UnmountedReading…
How a living cell becomes a specimen
One transaction, four things in order. The preview while you frame is drawn by this site; the slide itself, its cells, its price and its picture, comes from the contract.
- Frame
On the dish, open Fossilize and drag a frame across your own colony: 4 to 32 cells a side, wrapping at the edges as the dish does. The preview shows what would be kept.
- Capture
The contract reads the board at the generation your transaction lands in and keeps only your colony’s living cells inside the frame. Rivals and bare agar stay out. It needs a minimum number of them, set in the rules.
- Burn
Each captured cell burns a fixed amount of PETRI, set in the rules. The token’s storage is paid in NEAR; on free play it comes out of a guest’s sponsored credit.
- Mint
The slide becomes a NEP-171 token owned by the colony’s account, its picture an SVG inside the token’s own metadata. It can be kept, sent, or replanted as a pattern.
A picture anyone can check
The contract writes every slide into the dish’s one ordered ledger: the generation, the colony, the frame and the cells it captured. The replay on the verify page rebuilds the whole board from generation zero with the same Rust code the contract runs. When it reaches a slide, it checks that every cell on it was alive on the rebuilt board and owned by that colony, and that the PETRI burned matches the rules.
A slide of cells that never lived, or that belonged to someone else, would make the replay fail.
What a specimen does not say
- It shows one generation. The dish moves on; the colony on the slide may have died since.
- The replay checks how a slide was made. Who holds it now is an ordinary NEP-171 fact the contract reports.
- Replanting a slide’s pattern is an ordinary planting at the normal price. Holding the slide gives no discount and no claim on the spot.
An ordinary NEAR token
Specimens live in petri-v6.testnet on NEAR testnet, the dish contract itself, which implements the NEAR token standards. Any wallet or explorer that reads NEP-171 shows them; there is no separate collection contract and no file server.
- NEP-171
The core:
nft_tokenfor one slide,nft_transferandnft_transfer_callto send it. - NEP-177
Metadata: the title, and as media a
data:image/svg+xmlpicture the contract wrote. No IPFS link that can rot. - NEP-181
Enumeration:
nft_tokens,nft_tokens_for_ownerandnft_total_supply, to list them. - Explorer
NearBlocks lists every specimen on petri-v6.testnet, with each token’s owner and transfers.