Opal that keeps its host rock
Boulder opal is cut with natural host rock, commonly ironstone, remaining attached to the gem.
Sources · BOU-SRC-001 · BOU-SRC-007
Open Formation & GeologyEarth holds the color · BOU014
Boulder Opal Universe
Follow Queensland boulder opal through fields, formation, documented specimens, pattern language, interactive teaching systems, history, identification, collecting, typed discovery, evidence practice, and a rights-aware research archive.
Browse Boulder Opal Universe sections
Three ways in now
Start with stone, place or color.
BOU003 uses the verified BOU001 research corpus directly. It does not publish invented specimen records or pretend future tools are finished.
Queensland as a field system
BOU models multiple Queensland fields separately because their geology, concretion morphology and mining histories differ.
Sources · BOU-SRC-001 · BOU-SRC-007 · BOU-SRC-008
Open the AtlasPlay-of-color changes as you look
Viewing angle and lighting can change the visible play-of-color, making optics central to how opal is observed and evaluated.
Source · BOU-SRC-009
Follow the colorSpecimen anatomy
Read the rock and opal together.
Because host rock is integral to boulder opal, BOU specimen records are designed around host material, opal distribution and matrix relationships rather than treating every stone as a homogeneous gem.
Diagrammatic anatomy · not specimen evidence
Ironstone host
Queensland boulder opal can occur as veins or centre fillings in ironstone nodules or concretions.
Precious-opal layer
The Australian Museum describes boulder opal as a thin precious-opal layer indivisible from an ironstone matrix.
Potch
Potch is a miners’ term for common opal lacking play-of-color.
Queensland field records
Eight locality seeds, kept distinct.
The eight BOU001 locality seeds now have BOU004 field records. Current fossicking, tenure and access information is kept in a separate dated visitor layer and must still be checked before travel.
seed verifiedWintonSources · BOU-SRC-001 · BOU-SRC-002Open BOU004 field record →seed verifiedQuilpieSources · BOU-SRC-001 · BOU-SRC-002 · BOU-SRC-007Open BOU004 field record →seed verifiedYowahSources · BOU-SRC-002 · BOU-SRC-004 · BOU-SRC-007Open BOU004 field record →seed verifiedKoroitSources · BOU-SRC-007 · BOU-SRC-008Open BOU004 field record →seed verifiedOpaltonSources · BOU-SRC-005Open BOU004 field record →seed verifiedToompineSources · BOU-SRC-006Open BOU004 field record →seed referenceEuloSources · BOU-SRC-001 · BOU-SRC-007Open BOU004 field record →seed referenceKynunaSources · BOU-SRC-001 · BOU-SRC-003Open BOU004 field record →
Access boundary · BOU-CLM-022 · Queensland fossicking requires compliance with current licensing, land-access and tenure rules; active mining claims and leases can restrict access.
Optics + material
The spectrum is evidence, not decoration.
BOU’s interface uses spectral color sparingly because the subject itself is about color emerging from rock. The science remains explicit: opal is hydrated silica, and precious opal’s play-of-color is associated with ordered silica-sphere microstructure.
Boulder opal is cut with natural host rock, commonly ironstone, remaining attached to the gem.
Sources · BOU-SRC-001 · BOU-SRC-007
Opal is hydrated silica; precious opal’s play-of-color is produced by diffraction associated with ordered silica-sphere microstructure.
Sources · BOU-SRC-001 · BOU-SRC-010
Play-of-color can change with viewing angle and lighting and is central to opal appearance evaluation.
Sources · BOU-SRC-009
The Australian Museum characterizes boulder opal as a thin precious-opal layer indivisible from an ironstone matrix and identifies Queensland as its Australian source region.
Sources · BOU-SRC-011
Source-visible research
Every published fact can point back to a source ID.
These are the thirteen BOU001 research sources preserved into BOU003. They are references, not a blanket license to copy their photographs or other media. Media reuse remains asset-specific.
- BOU-SRC-001 · Opal | Geoscience AustraliaGeoscience Australia · research reference · checked 2026-09-10
- BOU-SRC-002 · Fossicking, gemstones and opal miningDepartment of Natural Resources and Mines, Manufacturing and Regional and Rural Development · research reference · checked 2026-09-10
- BOU-SRC-003 · Western opal fieldsQueensland Government · research reference · checked 2026-09-10
- BOU-SRC-004 · Yowah fossicking areaQueensland Government · research reference · checked 2026-09-10
- BOU-SRC-005 · Opalton designated fossicking landQueensland Government · research reference · checked 2026-09-10
- BOU-SRC-006 · Toompine designated fossicking landsQueensland Government · research reference · checked 2026-09-10
- BOU-SRC-007 · Queensland Opal Fields: Home of the Unique Australian Boulder OpalGemological Institute of America · research reference · checked 2026-09-10
- BOU-SRC-008 · Splendor in the Outback: A Visit to Australia’s Opal FieldsGems & Gemology / GIA · research reference · checked 2026-09-10
- BOU-SRC-009 · Opal Quality FactorsGemological Institute of America · research reference · checked 2026-09-10
- BOU-SRC-010 · Opal Gemstone | Opal StoneGemological Institute of America · research reference · checked 2026-09-10
- BOU-SRC-011 · Opal - The Australian MuseumAustralian Museum · research reference · checked 2026-09-10
- BOU-SRC-012 · GSQ reports and publicationsBusiness Queensland / Geological Survey of Queensland · research reference · checked 2026-09-10
- BOU-SRC-013 · Mining publications and videosBusiness Queensland · research reference · checked 2026-09-10
Released foundations + clearly planned next stages
What is live now.
Only released BOU systems are linked below. Tools remain planned and non-clickable until a later prompt implements and validates them.
Boulder Opal Atlas
Eight locality and field records with explicit current-source access boundaries.
Formation + Geology
Evidence-scoped geological explanations and a conceptual teaching model.
Specimen Cabinet + Patterns
Documented specimen records, rights-visible source presentation and pattern terminology with explicit evidence boundaries.
Interactive Specimen Lab
Toggle source-grounded anatomy concepts in a diagrammatic teaching model beside documented specimen metadata.
Lapidary Lab + Cut the Boulder
Compare authored viewing-face, host-retention and cutting-path trade-offs on a synthetic teaching rough with no real-stone cut prediction.
Mining, People & Historical Timeline
Source-classed chronology, field-history navigation and supported people/institution records with historical evidence kept separate from present-day access.
Identification + Care Literacy + Collector Evidence Notebook
Separate observation from determination, preserve conservative care boundaries and build an evidence record without photo authentication, appraisal or provenance guessing.
Evidence Relationship Explorer
Search and compare explicit typed relationships across fields, geology, documented specimens, patterns, Lab, lapidary, history, identification and collecting without similarity-based origin or value inference.
Games + Evidence Practice Lab
Replay evidence classification, formation order, field-guidance and descriptive-pattern challenges with local-only progress, no streaks, no prizes and a complete no-JS learning guide.
Research Archive
Search source-scoped geology, gemology, bibliography trails, archive records, long-tail research lanes and media-rights states without turning access or open licensing into provenance claims.
Evidence-first journey
Seven ways into the same material story.
Move from place and formation toward specimens and interpretation while keeping each evidentiary boundary visible.
Explore FieldsRegional geology, visitor guidance and source-backed locality records.Context ≠ provenanceUnderstand FormationFormation stages and locality-scoped geological examples.Model ≠ specimen historyInspect SpecimensDocumented records with source scope, rights and unknowns intact.Source before spectacleLearn Identification LimitsSeparate observation, documentation and expert-testing questions.No photo certificateStudy PatternsDescriptive visual vocabulary without mine or value inference.Description onlyLapidary ContextUnderstand cutting trade-offs on a synthetic teaching rough.No real-stone cut planResearch PracticeTrace sources, rights, bibliography leads and escalation points.Evidence stays scoped
ICU / CONNECTED DISCOVERY
Continue through related ideas.
These are bounded editorial connections; paid placement does not influence them.
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Across ICU · explainable bridges
Continue into another specialist world.
These are reviewed cross-universe connections with an explicit relationship type and uncertainty boundary. A bridge is not a claim of influence, causation, or shared taxonomy.