Drake's Plate of Brass: The E Clampus Vitus Forgery

Hoax/ForgeryAnomalous Material Scientific Analysis

Evidence Dossier

Legacy category: Hoax / Forgery

Drake's Plate of Brass: The E Clampus Vitus Forgery

Evidence Dossier: A record proves that a statement, transfer, examination, or result was documented. It does not automatically prove the anomalous interpretation attached to it.

Overview Evidence Timeline Analysis Sources

Date(s) 1933, 1936-06-28, 1937-04-06, 1938-12-15, 1977-07-27, 2003-02-18

Location(s) Marin County, California, San Francisco Bay Area, California

Investigative Scepticism (Scully Score) 10/10

Anomalous Plausibility (Mulder Score) 1/10

Reported Claim Drake's Plate of Brass had a false purported origin of 1579; staged evidence supports its fabrication from modern materials in the twentieth century.

Evidence Evaluation Strength Strong documentary and scientific evidence supports a twentieth-century forgery. The staged record includes the discovery claim, early mistaken metallurgical authentication, a retrospective finder interview, and Lawrence Berkeley National Laboratory's corrective account of the 1977 analysis.

Investigative Assessments

AGENT MULDER ASSESSMENT

"The reported claim remains worth testing against the record: Drake's Plate of Brass had a false purported origin of 1579; staged evidence supports its fabrication from modern materials in the twentieth century. The strongest documented reasons to keep the file open are: Drake's Plate of Brass Discovery Report: It details the location, discovery story, and historical argument for authenticity; Drake's Plate of Brass Authenticated Report: It documents early chemical testing that erroneously supported authenticity. Key unresolved lead: What specific engraving tools were used by the forgers to simulate sixteenth-century lettering?"

AGENT SCULLY ASSESSMENT

"Evidentiary limitations: Strong documentary and scientific evidence supports a twentieth-century forgery. The staged record includes the discovery claim, early mistaken metallurgical authentication, a retrospective finder interview, and Lawrence Berkeley National Laboratory's corrective account of the 1977 analysis. Note that: Drake's Plate of Brass Discovery Report fails to support: It does not establish honest provenience or prove the plate is genuine; Drake's Plate of Brass Authenticated Report fails to support: Its results were disproven by modern testing and it did not detect the twentieth-century brass composition. Documented contradiction: The plate inscription uses twentieth-century lettering techniques and modern spelling styles, conflicting with authentic sixteenth-century English records. Leading conventional hypothesis: The plate is a modern forgery prepared in the 1930s as a practical joke."

Case Summary

In 1936, a brass plate was discovered in Marin County, California, purporting to be the tablet left by Sir Francis Drake in 1579 to claim the region for Queen Elizabeth I. Herbert Bolton and the California Historical Society promoted the find as authentic. A 1938 metallurgical study also supported it. In 1977, Helen Michel and Frank Asaro found a modern brass composition, and in 2003 historians presented documentary evidence that members of E Clampus Vitus had devised the object as a practical joke.

Evidence Locker

4 inspectable evidence items. Claims and source findings are kept separate.

Complete 1937 journal volume scan Local copy hash-verified Complete source

Drake's Plate of Brass Discovery Report

Analyst rating: Original contemporary discovery announcement and documentation

“the relic is of solid brass about five inches wide by eight inches long and an eighth of an inch thick it was picked up by beryle shinn in the summer of 1936”

Record locationPrinted page 1; PDF page 9

Evidence classcontemporary report

Relationship to claimContains the original academic claim and transcription of the plate.

Authenticity assessmentAuthentic digitization of the 1937 journal volume.

What this supportsIt details the location, discovery story, and historical argument for authenticity.

What it does not supportIt does not establish honest provenience or prove the plate is genuine.

ProvenanceCalifornia Historical Society Quarterly digitized by Internet Archive.

Chain of custodyPublished in 1937, digitized by Internet Archive, hash-verified local PDF.

Source completenessComplete. Staged file is the complete volume scan as distributed.
Known gaps: No known completeness gaps recorded.

Open Complete Source (Local PDF Document) Download Copy Canonical Agency Record

Complete 1938 journal volume scan Local copy hash-verified Complete source

Drake's Plate of Brass Authenticated Report

Analyst rating: Metallurgical analysis claiming authentication

“announcement of the finding of the plate was made at a meeting of the california historical society held april 6 1937”

Record locationPrinted page 7; PDF page 7

Evidence classscientific analysis

Relationship to claimRepresents the initial scientific analysis that validated the forgery.

Authenticity assessmentAuthentic digitization of the 1938 special publication volume.

What this supportsIt documents early chemical testing that erroneously supported authenticity.

What it does not supportIts results were disproven by modern testing and it did not detect the twentieth-century brass composition.

ProvenanceCalifornia Historical Society Quarterly Special Publication 14 digitized by Internet Archive.

Chain of custodyPublished in 1938, digitized by Internet Archive, hash-verified local PDF.

Source completenessComplete. Staged file is the complete volume scan as distributed.
Known gaps: No known completeness gaps recorded.

Open Complete Source (Local PDF Document) Download Copy Canonical Agency Record

Complete oral history interview transcript PDF Local copy hash-verified Complete source

William Caldeira Oral History Transcript

Analyst rating: Witness description of earlier 1933 discovery

“if the object mr caldeira had found was the plate then in all probabilitydrake had stopped on drake s bay”

Record locationPrinted page 2; PDF page 4

Evidence classwitness account

Relationship to claimEstablishes the claimed find and movement history of the plate between 1933 and 1936.

Authenticity assessmentAuthentic digitization of the Bancroft Library transcript.

What this supportsIt shows the plate was found in 1933 near Point Reyes and discarded near San Quentin.

What it does not supportIt relies on retrospective memory and does not determine who made the plate.

ProvenanceBancroft Library oral history collection digitized by Internet Archive.

Chain of custodyRecorded in 1955-1956, digitized by Internet Archive, hash-verified local PDF.

Source completenessComplete. Staged file is the complete interview transcript scan.
Known gaps: No known completeness gaps recorded.

Open Complete Source (Local PDF Document) Download Copy Canonical Agency Record

Complete Lawrence Berkeley National Laboratory web article HTML Local copy hash-verified Complete source

Drake's Plate, the end of the mystery?

Analyst rating: Official laboratory account of the 1977 neutron activation analysis and 2003 historical findings

“That was the case until 1977, when Berkeley Lab's Helen Michel and Frank Asaro used neutron activation analysis on the brass plate and found that it was most probably manufactured between the last half of the nineteenth century and the early part of the twentieth.”

Record locationParagraph beginning 'That was the case until 1977' in the complete HTML article

Evidence classOfficial scientific corrective account

Relationship to claimSummarizes the direct laboratory analysis that rejected a sixteenth-century origin.

Authenticity assessmentStrong for the LBL institutional publication; the article summarizes rather than reproduces the full lab report.

What this supportsIt reports that Michel and Asaro found the plate's brass to be modern and explains the impurity and manufacturing evidence.

What it does not supportIt is a retrospective institutional account, not the complete 1977 laboratory report or the physical plate.

ProvenanceLawrence Berkeley National Laboratory Science Beat archive, dated April 4, 2003.

Chain of custody2003 Berkeley Lab web publication to live LBL archive to unmodified hash-verified local HTML.

Source completenessComplete. The staged file is the complete HTML response distributed at the acquisition URL.
Known gaps: No known completeness gaps recorded.

Open Complete Source (Local HTML Media) Download Copy Canonical Agency Record

Documented Timeline

1933: Chauffeur William Caldeira finds a brass plate near Drake's Bay but discards it near San Quentin.
June 28, 1936: Beryl Shinn finds the brass plate near San Quentin and keeps it for several months.
April 6, 1937: Professor Herbert Bolton announces the discovery to the California Historical Society.
December 15, 1938: Colin Fink and E. P. Polushkin publish their metallurgical authentication report.
July 27, 1977: Helen Michel and Frank Asaro publish the Lawrence Berkeley Laboratory report proving the brass is modern.
February 18, 2003: Historians presented documentary evidence linking the practical joke to members of E Clampus Vitus.

Named Participants and Roles

Beryl Shinn, Finder of the plate in 1936. Account basis: Contemporaneous. Witness quality: Moderate. Shinn claimed to have found the plate and kept it for months before showing it to Bolton. Evidence: drakes_plate_discovery
William Caldeira, Earlier finder in 1933. Account basis: Retrospective. Witness quality: Moderate. His oral history recorded in 1955 gives details of his 1933 find, though it was recorded years after the events. Evidence: drakes_plate_caldeira

Contradictions and Record Conflicts

The plate inscription uses twentieth-century lettering techniques and modern spelling styles, conflicting with authentic sixteenth-century English records.
Early chemical tests by Fink in 1938 declared the metal authentic, but more precise neutron activation analysis in 1977 proved it was modern American brass.

Conventional Explanations

The plate is a modern forgery prepared in the 1930s as a practical joke.
Evidence for: Neutron activation analysis shows high zinc content and low impurities consistent with modern brass. Microscope examination shows modern cutting marks.
Limits: Physical testing confirms the forgery but does not identify the specific individuals who engraved the letters.
Evidence: lbl_drakes_plate_analysis, drakes_plate_caldeira

Evidence Stance Matrix

Hypothesis	Stance	Rationale	Evidence IDs
The plate was an authentic sixteenth-century artifact left by Sir Francis Drake.	Challenges	Chemical composition and microstructural features exclude a sixteenth-century origin, showing it was most probably manufactured in the late nineteenth or early twentieth century.	drakes_plate_caldeira, lbl_drakes_plate_analysis
The plate was a twentieth-century forgery created by members of E Clampus Vitus as a prank.	Supports	Laboratory analysis confirms the brass is modern, supporting a twentieth-century fabrication, and historical testimonies trace its planted discovery, though identifying the specific pranksters relies on historical rather than chemical evidence.	drakes_plate_discovery, drakes_plate_caldeira, lbl_drakes_plate_analysis

Missing Evidence

The original drawing or mockup of the plate design used by the forgers.
It would conclusively show the design process and identify all the E Clampus Vitus members involved.
The full 1977 laboratory report, raw neutron-activation results, calibration and QC records, sample custody, and the physical plate
Required for independent replication of the scientific findings; only the institutional summary is staged.

What Remains Unresolved

The exact role and knowledge of each member of the E Clampus Vitus circle in the hoax.
Most participants took the joke to their graves, leaving only circumstantial historical evidence of individual actions.

Investigative Hypotheses

The plate was an authentic sixteenth-century artifact left by Sir Francis Drake.
The plate was a twentieth-century forgery created by members of E Clampus Vitus as a prank.

Open Questions

What specific engraving tools were used by the forgers to simulate sixteenth-century lettering?
Are there surviving private papers of G. Ezra Dane detailing the design of the plate?