OpenGlyph — Catalogue of the American Public DomainJurisdiction: United StatesRev. 2026.08
Images / art

Two archives, queried live.

Every record below comes from The Met or Smithsonian Open Access and was filtered on that archive’s own rights field before it reached this page. 12 shown for “Phormidium cataractarum Rabenh.” — 40 records examined, 8 dropped by the rights gate.

Archives queried 2026-09-10 18:21 UTC · fetched live for this request

Object
Public domainThe Met’s isPublicDomain field is true for this object.
CC0 (public-domain equivalent)Smithsonian’s metadata_usage.access reads CC0 — a waiver, not an expired term.
Not shownAnything failing its archive’s rights field is dropped server-side and never appears here.
Phormidium cataractarum Rabenh.

Phormidium cataractarum Rabenh.

Artist not stated in the record

CC0 (public-domain equivalent)Smithsonian
Phormidium cataractarum Rabenh.

Phormidium cataractarum Rabenh.

Artist not stated in the record

CC0 (public-domain equivalent)Smithsonian
Phormidium nubecula Stizenb. & Rabenh. in Rabenh.

Phormidium nubecula Stizenb. & Rabenh. in Rabenh.

Artist not stated in the record · Sep 1854

CC0 (public-domain equivalent)Smithsonian
Phormidium moerlianum Grunow in Rabenh.

Phormidium moerlianum Grunow in Rabenh.

Artist not stated in the record · 1863

CC0 (public-domain equivalent)Smithsonian
Phormidium membranaceum var. viale Rabenh.

Phormidium membranaceum var. viale Rabenh.

Artist not stated in the record · -- Sum ----

CC0 (public-domain equivalent)Smithsonian
Phormidium haussknechtianum Rabenh. in Hausskn.

Phormidium haussknechtianum Rabenh. in Hausskn.

Artist not stated in the record · 1869

CC0 (public-domain equivalent)Smithsonian
Phormidium vulgare f. imberbe Stizenb. in Rabenh.

Phormidium vulgare f. imberbe Stizenb. in Rabenh.

Artist not stated in the record · Nov 1857

CC0 (public-domain equivalent)Smithsonian
Phormidium subfuscum var. membranaceum Rabenh.

Phormidium subfuscum var. membranaceum Rabenh.

Artist not stated in the record · Sep 1864

CC0 (public-domain equivalent)Smithsonian
Phormidium aeruginosum var. membranaceum Grunow in Rabenh.

Phormidium aeruginosum var. membranaceum Grunow in Rabenh.

Artist not stated in the record · Aug 1835

CC0 (public-domain equivalent)Smithsonian
Phormidium versicolor Wartm. in Rabenh.

Phormidium versicolor Wartm. in Rabenh.

Artist not stated in the record · 1 Oct 1859

CC0 (public-domain equivalent)Smithsonian
Oscillatoria irrigua var. subsalsa Grunow in Rabenh.

Oscillatoria irrigua var. subsalsa Grunow in Rabenh.

Artist not stated in the record · Feb 1861

CC0 (public-domain equivalent)Smithsonian
Chlorotylium cataractarum var. submarinum Hansg.

Chlorotylium cataractarum var. submarinum Hansg.

Artist not stated in the record · 1891

CC0 (public-domain equivalent)Smithsonian
What was queried

Where these records came from.

Two archives are wired, and only two. Each one is filtered on its own rights field — never on a title match, and never on the presence of an image file.

  • The Met Collection API (Open Access)Rights field: isPublicDomain. The archive returned no records for this term.0 matched
  • Smithsonian Open Access API (api.si.edu)Rights field: content.descriptiveNonRepeating.metadata_usage.access. 1786 matched · 40 examined · 8 dropped by the rights gate. Kept only where metadata_usage.access === "CC0" and an image resource was published.12 shown

These figures describe the pass run at 2026-09-10 18:21 UTC, during this request. A completed pass is kept for 24 hours and replayed for an identical search, which is what keeps repeated queries inside Smithsonian’s 30-requests-per-hour allowance. A pass in which either archive failed to answer is never kept — an outage must not be replayed as though it were a finding about the catalogue.

Wikimedia Commons and the Library of Congress are deliberately not wired. Wikimedia was confirmed, on a live query, to return CC-BY material inside the same result set as genuine public domain works, and filtering it safely has not been designed yet. loc.gov was blocked by bot detection during the source evaluation, so its rights vocabulary has never been observed — and nothing here is built on a field nobody has read.

An image file is a rights claim. It never travels without its field.