Identify weathered glass, understand the clues it carries, and preserve the known provenance of each find.
Storms and shifting waves can expose fresh material along the waterline. Look where small stones collect; identification is based on observable clues, not color alone.
A few quick observations build a Lake Michigan-specific reading.
Choose the closest physical feature you can see.
These are recorded as known provenance. The app keeps them separate from inferred history.
Likely an aqua utility-bottle fragment, softened by prolonged Lake Michigan tumbling.
Aqua is the natural tint of many older utility glasses and is a familiar Lake Michigan find.
The evidence is split. One more physical clue could change this reading.
Local context can strengthen or weaken a color-based hypothesis.
Lake Michigan shoreline history provides context, not certainty.
Lakeglass uses multiple regional and beach-glass references for this reading.
This reading combines color, thickness, surface condition, and shoreline context. It is historically informed rather than lab-grade dating.
A saved Lake Michigan specimen with known find context and an inferred historical reading.
Color, form, opacity, thickness, and surface clues are preserved with the accession.
Use these when a specimen lands between two possible readings.
Finish style and seam position can narrow manufacturing period.
A rough or polished base scar can signal older hand-finished production.
Letters, numbers, and logos can point to a maker or regional bottler.
Irregular bubbles can support an older-manufacture hypothesis, but are not proof alone.
Opaque white may indicate milk glass rather than frosted clear glass.
Hold it to strong light; deep olive or amber can look black at thickness.
Spring, fall, and strong wave events can reshape the shoreline and expose new glass.
Search where small stones gather near the waterline; glass often settles with material of similar size.
Thickness, lighting, weathering, and glass chemistry can all shift how a color appears.
Leland Blue and similar material are industrial smelting slag, not ordinary bottle glass.
1–2 common · 3–4 familiar · 5–6 uncommon · 7–8 rare · 9 very rare · 10 exceptional. The scale is a comparative Lakeglass field index and can be revised as better regional evidence becomes available.
A field identification is an interpretation of physical clues, not a laboratory attribution.
Lakeglass compares color, opacity, thickness, form, surface wear, markings, and shoreline context. When a diagnostic feature such as a rim, base, embossing, near-black color, milk glass, or slag candidate is reported, the guide asks one additional targeted question because those clues can carry more historical weight than color alone.
Possible · Good match · Strong match ÷ Distinctive match. These labels describe how well the observed clues agree; they are not statistical probabilities.
The 1–10 score is a comparative Lakeglass field index for how often a color is encountered around Lake Michigan. It is not a measured population frequency and can change as better regional evidence becomes available.
Where and when you found a specimen are recorded as known provenance. Probable source, age, and historical origin remain inferred interpretations and may change when better evidence appears.
A fragment usually cannot be dated or assigned to a specific manufacturer from color alone. Embossing, bottle finishes, bases, mold seams, and other diagnostic features can substantially strengthen a reading.
Lakeglass cross-checks its field notes against Beachcombing Magazine, Rock & Gem, Schlitz Audubon Nature Center, Visit Southwest Michigan, Michigan Beachtowns, and regional Michigan reporting. Regional observations are used as context rather than treated as universal rules, and source-backed information is rewritten into concise field-guide language.
Lakeglass is structured so the field guide, identification logic, and collection can live on-device without an account.
Saved accession records are persisted locally in the browser using IndexedDB, so they can survive normal page reloads on the same device.
Local archive enabledThe identification data and research notes are already bundled into the app. A production deployment only needs a service worker and cache manifest to make those screens available without a connection.
Ready for cachingThe Lakeglass production package is ready to be split into a web-app manifest, service worker, app icons, and this interface for a real home-screen install.
Ready to packageNo camera identification, photo uploads, or cloud profile are needed for version 1. Export and import remain the backup path for moving a collection between devices.