{"id":8052761,"record_url":"https://metalstack.app/8052761","status":"listed","algorithm":"SHA-256","record_hash":"0da4ebb7d50d54cd4fc860b4b024107e01757a467bb06dd0ed00ef2b4da63a5a","record_hash_recomputed":"0da4ebb7d50d54cd4fc860b4b024107e01757a467bb06dd0ed00ef2b4da63a5a","matches":true,"record_hash_method":"record_hash = SHA-256(utf8(canonical)). The `canonical` string below is the exact, verbatim preimage — recompute it yourself and compare.","canonical":"{\"id\":8052761,\"title\":\"1921 UK Florin\",\"metal\":\"silver\",\"fineness\":\".500\",\"weight_g\":11.28,\"dims_mm\":\"D28.5 x 2.3\",\"year\":\"1921\",\"checks\":[{\"type\":\"composition\",\"instrument\":\"XRF-01\",\"result\":\"pass\",\"reading\":\"Ag 50.2%\",\"tested_at\":\"2026-06-11\"},{\"type\":\"conductivity\",\"instrument\":\"PMV-01\",\"result\":\"pass\",\"reading\":\"Ag .500 ✓\",\"tested_at\":\"2026-06-11\"},{\"type\":\"dimensions\",\"instrument\":\"CAL-01\",\"result\":\"pass\",\"reading\":\"D28.5 x 2.3 mm - matches published spec\",\"tested_at\":\"2026-06-11\"},{\"type\":\"inspection\",\"instrument\":null,\"result\":\"pass\",\"reading\":\"Design, edge and marks consistent with a genuine example; no plating wear; no concerns under magnification/UV\",\"tested_at\":\"2026-06-11\"},{\"type\":\"magnet\",\"instrument\":null,\"result\":\"pass\",\"reading\":\"Non-magnetic; eddy-slide consistent with high-conductivity metal\",\"tested_at\":\"2026-06-11\"},{\"type\":\"ping\",\"instrument\":null,\"result\":\"pass\",\"reading\":\"Resonance within expected profile\",\"tested_at\":\"2026-06-11\"},{\"type\":\"weight\",\"instrument\":\"SCALE-01\",\"result\":\"pass\",\"reading\":\"11.28 g\",\"tested_at\":\"2026-06-11\"}],\"images\":[],\"seal\":true}","event_chain_method":"chain_hash = SHA-256(prev_chain_hash + '|' + item_id + '|' + event_type + '|' + detail + '|' + created_at). prev_chain_hash is '' for the first event; each event's prev_chain_hash must equal the previous event's chain_hash.","events":[{"created_at":"2026-06-11 09:42:10","event_type":"intake","detail":"Item received into intake","prev_chain_hash":null,"chain_hash":"224d357f627a525ae8401c5af028aee32d4f61b0d7ef103f7edaec0e63c8d831"},{"created_at":"2026-06-11 09:48:31","event_type":"check_recorded","detail":"Weighed: 11.28 g - SCALE-01, operator PS","prev_chain_hash":"224d357f627a525ae8401c5af028aee32d4f61b0d7ef103f7edaec0e63c8d831","chain_hash":"0af03e0c7c13c0c668cd72f9ca89c71a8baa633426758d0b3087c2350048bc44"},{"created_at":"2026-06-11 09:51:07","event_type":"check_recorded","detail":"Magnet & eddy-slide: non-magnetic, high-conductivity response","prev_chain_hash":"0af03e0c7c13c0c668cd72f9ca89c71a8baa633426758d0b3087c2350048bc44","chain_hash":"9411ba2b184e52f7e693a6beb92e7cccf55645e237511f95f36b278ee820d8f6"},{"created_at":"2026-06-11 09:54:20","event_type":"check_recorded","detail":"Composition: Ag 50.2% - XRF-01, operator PS","prev_chain_hash":"9411ba2b184e52f7e693a6beb92e7cccf55645e237511f95f36b278ee820d8f6","chain_hash":"c589bee4239bae4522aa2389044ad1eb04868fc4ea7f0bcc1d9fe6e0e6cc054c"},{"created_at":"2026-06-11 09:56:40","event_type":"check_recorded","detail":"Conductivity (secondary): Ag .500 ✓ - PMV-01 (Sigma)","prev_chain_hash":"c589bee4239bae4522aa2389044ad1eb04868fc4ea7f0bcc1d9fe6e0e6cc054c","chain_hash":"4561635f7e1b0e041f4891359f5a5e3428493ea8dcf92d81c6e142bd706765d9"},{"created_at":"2026-06-11 10:00:05","event_type":"check_recorded","detail":"Inspection: marks & construction consistent; no plating wear","prev_chain_hash":"4561635f7e1b0e041f4891359f5a5e3428493ea8dcf92d81c6e142bd706765d9","chain_hash":"c7310fbda270ae4f0cb173a29a4593c8cdcd6e36068be55b1276018b45469878"},{"created_at":"2026-06-11 10:02:40","event_type":"check_recorded","detail":"Supplementary: dimensions D28.5 x 2.3 mm match spec; ping within profile","prev_chain_hash":"c7310fbda270ae4f0cb173a29a4593c8cdcd6e36068be55b1276018b45469878","chain_hash":"0b96f9b778160976f815963dd2c4c8461e14370310f0f30b7e5948836bfb382f"},{"created_at":"2026-06-11 10:08:15","event_type":"seal_applied","detail":"Tamper-evident hologram seal applied","prev_chain_hash":"0b96f9b778160976f815963dd2c4c8461e14370310f0f30b7e5948836bfb382f","chain_hash":"c3c14a0fb8335f51a52310522025897f1051a4ce94a0e397059c015872bdb3a1"},{"created_at":"2026-06-11 10:11:23","event_type":"status_change","detail":"Record published - status: verified","prev_chain_hash":"c3c14a0fb8335f51a52310522025897f1051a4ce94a0e397059c015872bdb3a1","chain_hash":"2995f052d0868facb647d28d74505d52e68a391a58b712b831d90167fd8df79a"},{"created_at":"2026-06-11 10:14:02","event_type":"card_issued","detail":"Verification card MS-8052761 issued","prev_chain_hash":"2995f052d0868facb647d28d74505d52e68a391a58b712b831d90167fd8df79a","chain_hash":"e20b74d2ce588520f9d1a86b5cdc234278bcf0612476fbf6de0257fab5641526"},{"created_at":"2026-06-11 12:30:00","event_type":"status_change","detail":"Listed for sale","prev_chain_hash":"e20b74d2ce588520f9d1a86b5cdc234278bcf0612476fbf6de0257fab5641526","chain_hash":"4cbc643e40cbaed769f9b69ed45738ce0eb54825b1c072459fb8580d2ee0c628"}]}