{"id":4478023,"record_url":"https://metalstack.app/4478023","status":"listed","algorithm":"SHA-256","record_hash":"547742c76923025a35754905aa41e74714c7da2f9dd5d12b5e87e8557d5a658c","record_hash_recomputed":"547742c76923025a35754905aa41e74714c7da2f9dd5d12b5e87e8557d5a658c","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\":4478023,\"title\":\"100 g Cast Silver Bar\",\"metal\":\"silver\",\"fineness\":\".999\",\"weight_g\":99.97,\"dims_mm\":\"50.6 x 29.2 x 7.1\",\"year\":null,\"checks\":[{\"type\":\"composition\",\"instrument\":\"XRF-01\",\"result\":\"pass\",\"reading\":\"Ag 99.92%\",\"tested_at\":\"2026-06-12\"},{\"type\":\"conductivity\",\"instrument\":\"PMV-01\",\"result\":\"pass\",\"reading\":\"Ag .999 ✓\",\"tested_at\":\"2026-06-12\"},{\"type\":\"dimensions\",\"instrument\":\"CAL-01\",\"result\":\"pass\",\"reading\":\"50.6 x 29.2 x 7.1 mm - matches published spec\",\"tested_at\":\"2026-06-12\"},{\"type\":\"inspection\",\"instrument\":null,\"result\":\"pass\",\"reading\":\"Stamps and construction consistent; no plating wear or seams of concern under magnification/UV\",\"tested_at\":\"2026-06-12\"},{\"type\":\"magnet\",\"instrument\":null,\"result\":\"pass\",\"reading\":\"Non-magnetic; eddy-slide consistent with high-conductivity metal\",\"tested_at\":\"2026-06-12\"},{\"type\":\"weight\",\"instrument\":\"SCALE-01\",\"result\":\"pass\",\"reading\":\"99.97 g\",\"tested_at\":\"2026-06-12\"}],\"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":"2026-06-12 09:42:10","event_type":"intake","detail":"Item received into intake","prev_chain_hash":null,"chain_hash":"8a32d937ca9968a717e35cc2a5d333b92e3c8b9e6e575a556b1ed1fefa01e52d"},{"created_at":"2026-06-12 09:48:31","event_type":"check_recorded","detail":"Weighed: 99.97 g - SCALE-01, operator PS","prev_chain_hash":"8a32d937ca9968a717e35cc2a5d333b92e3c8b9e6e575a556b1ed1fefa01e52d","chain_hash":"235a5a645f567a85a27ba7f527a4ebea5e45296c952d2be6572b81c915577f00"},{"created_at":"2026-06-12 09:51:07","event_type":"check_recorded","detail":"Magnet & eddy-slide: non-magnetic, high-conductivity response","prev_chain_hash":"235a5a645f567a85a27ba7f527a4ebea5e45296c952d2be6572b81c915577f00","chain_hash":"1a71b9b6425efa0da8ae27dbf4469a15f072e76ab284d7450507eaeacb040237"},{"created_at":"2026-06-12 09:54:20","event_type":"check_recorded","detail":"Composition: Ag 99.92% - XRF-01, operator PS","prev_chain_hash":"1a71b9b6425efa0da8ae27dbf4469a15f072e76ab284d7450507eaeacb040237","chain_hash":"80c119a141a3e284a4d2c953954dd47948ecf3a39a8b4bf0dbfc491e0e020826"},{"created_at":"2026-06-12 09:56:40","event_type":"check_recorded","detail":"Conductivity (secondary): Ag .999 ✓ - PMV-01 (Sigma)","prev_chain_hash":"80c119a141a3e284a4d2c953954dd47948ecf3a39a8b4bf0dbfc491e0e020826","chain_hash":"6a6d5e12b34dab71aa9571fdd20f6c46d920a88019ff34c3bd554cef2b735390"},{"created_at":"2026-06-12 10:00:05","event_type":"check_recorded","detail":"Inspection: marks & construction consistent; no plating wear","prev_chain_hash":"6a6d5e12b34dab71aa9571fdd20f6c46d920a88019ff34c3bd554cef2b735390","chain_hash":"4cd33e5459cd9796a7051a0c3f00ba10f78bb5c2c1c101e48570e587e7ec41f0"},{"created_at":"2026-06-12 10:02:40","event_type":"check_recorded","detail":"Supplementary: dimensions 50.6 x 29.2 x 7.1 mm match spec","prev_chain_hash":"4cd33e5459cd9796a7051a0c3f00ba10f78bb5c2c1c101e48570e587e7ec41f0","chain_hash":"c6d1457d7166912f4d8bec51dcbfc578c9541143ea748c1826b79dd66439e3b5"},{"created_at":"2026-06-12 10:08:15","event_type":"seal_applied","detail":"Tamper-evident hologram seal applied","prev_chain_hash":"c6d1457d7166912f4d8bec51dcbfc578c9541143ea748c1826b79dd66439e3b5","chain_hash":"f8eac00b3a876b8be1c544fdf718ba77d625a63ed33717d661536c9463ea4c5c"},{"created_at":"2026-06-12 10:11:23","event_type":"status_change","detail":"Record published - status: verified","prev_chain_hash":"f8eac00b3a876b8be1c544fdf718ba77d625a63ed33717d661536c9463ea4c5c","chain_hash":"c0824071ba19a32569bb84fcb85ce4db55051eddb337803e6694da49d98edb2a"},{"created_at":"2026-06-12 10:14:02","event_type":"card_issued","detail":"Verification card MS-4478023 issued","prev_chain_hash":"c0824071ba19a32569bb84fcb85ce4db55051eddb337803e6694da49d98edb2a","chain_hash":"b2eedf54fbff8130df26235876e9d53cafc7c854175dc1e59fe4fca995c85caf"},{"created_at":"2026-06-12 12:30:00","event_type":"status_change","detail":"Listed for sale","prev_chain_hash":"b2eedf54fbff8130df26235876e9d53cafc7c854175dc1e59fe4fca995c85caf","chain_hash":"b91cb5068d00c59033e2bb262340777e0c78d567ee95d3eaee096c35d6f75af7"}]}