LBMA Gold Price (dataset)

The twice-daily London benchmark fix (AM/PM, USD/oz). Our gold-leg backbone: daily PM fix 1968-04→, month-end extraction for the monthly gold/SPX study family. This page is the canonical record of the feed’s status and our fallback architecture — all gold-leg protocols cite it.

Status: no free live fix feed exists (verified 2026-10-12)

The official series still exists but is licensed-only, and every public route to it is dead:

Route	Status	Evidence (2026-10-12)
FRED GOLDPMGBD228NLBM	dead	IBA series dropped 2022-01-31 (HTTP 404)
Nasdaq Data Link LBMA/GOLD	dead	dataset delisted (page 404; catalog empty)
prices.lbma.org.uk/json/gold_pm.json	bot-walled	Incapsula 403, incl. from a real browser
Public GitHub mirrors	frozen	they pull the walled JSON above
LBMA paid successor (LBMTD)	wrong product	OTC volumes, not price

The mirror this brain used as PRIMARY — unbalancedparentheses/forex-centuries data/sources/lbma/lbma_gold_daily.csv (weekly CI pulling the LBMA JSON) — died when the wall went up: last data row 2026-02-25, last commit 2026-02-26. Frozen copy pinned: sha256 86057834bd6fca539749f150a42255e28c4cf0fac2935b265b1c13e826fb24d9.

Ecosystem corroboration (what other projects did): datahub’s core/gold-prices fell back to monthly averages (World Bank Pink Sheet) after the Timothy Green historical PDF went behind a login; its updater runs daily but can only refresh averages. Free daily fix data, post-Feb-2026, exists nowhere maintained.

What IS alive (probed 2026-10-12)

• Yahoo GC=F COMEX front-month close — daily, current to today; from 2000-09.
• Yahoo GLD adj close (NAV total-return proxy, ~0.4%/yr expense drag) — daily, current to today; from 2004-12.
• World Bank Pink Sheet monthly average USD/oz (CC BY 4.0), current; mirrors: eco3min.fr CSV (0.0% dev vs xlsx, current to 2026-09) and datahub core/gold-prices (updated 2026-10-04). Averages — cross-check only, not signal-grade.

Our gold-leg architecture (adopted 2026-10-12)

1. History 1968-04 → 2026-02: frozen mirror above. Immutable by construction (sha-pinned); triple-validation vs the FRED-era dump (0.0004% mean dev), Pink Sheet monthly means (0.06% median), and GC=F month-ends was recorded 2026-10-12 and is re-runnable from the fetch script.
2. Live extension 2026-03 →: month-end signals computed on GLD total returns (primary; cleanest spot proxy that is current and daily), with GC=F month-ends as second opinion. Splice is ratio-normalized at the seam — same treatment as Shiller↔Yahoo for SPX — and studies run on within-series returns, never raw spliced levels.
3. Cross-check every month: composite month vs Pink Sheet monthly average; flag if |deviation| > 1%.

Basis, measured (month-end GC=F vs frozen fix, 2000-10→2026-01, 260 months): median 0.36%, p90 1.21%, max 4.75% at 2026-01 — the seam window IS the worst basis month in the record (spot outran futures in the Jan-2026 squeeze), which is why naive level-splicing is banned and the cross-check is mandatory.

Extension-leg fidelity (measured 2026-10-12): monthly GLD-TR vs fix returns over 2004-12→2026-02 (254 mo): corr 0.974, |diff| median 0.55%, p90 1.79%. Part of this gap is structural timing, not error: the fix prices London 15:00 while GC=F/GLD price the NY 16:00 close — any proxy we can get free prices a different clock. Treat sub-~1%/month proxy-vs-fix differences as the noise floor when reading gold-leg results.

Constraints accepted

• True daily PM fixes after 2026-02 are unavailable free: daily-MA / whipsaw legs extend on GLD/GC=F basis, documented per study. Full-history daily remains frozen history only.
• The honest fix-grade continuation is a paid licensed feed (metals-api / MetalPriceAPI / EODHD XAU.USD class, ~$20–50/mo). Not adopted yet — decision point if a verdict ever hinges on fix-vs-proxy fidelity after Feb-2026.
• Vendor numbers quoted from sources that used LBMA fixes (Returnstream, QuantifiedStrategies) stay recorded as attributed facts; our replications run on the composite above.

Cite as

entities/lbma-gold-price.md — gold-leg source hierarchy + frozen-history pin. Update updated: and append a dated status line here whenever a feed’s state changes; fetch-script headers in receipts-lab mirror this page.