Cabinet No. 40 vs Earthwonders - Mineral Management Software Comparison

"Mineral collection software" can mean very different things. Some tools are built around deep, customizable cataloging of your collection. Others are built around a community marketplace with a lightweight catalog attached. Cabinet No. 40 and Earthwonders sit on opposite ends of that spectrum, which makes the comparison genuinely useful rather than a feature-for-feature draw.

This article sticks to publicly verifiable facts from both platforms' websites and help centers. Where information is not public, we say so explicitly.

Why this comparison matters

If you have ever tried to catalog more than a hundred specimens, you already know that a spreadsheet stops being fun around entry number forty-seven. The question is not whether you need software - it is which kind of software matches how you actually work with your collection.

Earthwonders and Cabinet No. 40 represent two fundamentally different philosophies. One is a marketplace that happens to let you list your stones. The other is a collection-management system that happens to let you sell them. Understanding that distinction saves you from choosing a tool that solves the wrong problem.

Cabinet No. 40 in a nutshell

Cabinet No. 40 (C40) is a collection-management platform for serious mineral collectors, built as a web app with full mobile support and an offline Field Mode. The Collector Panel is the core product; the marketplace is a separate, optional layer.

What defines C40:

• OpenMindat API sync and automation. When you start typing a mineral name, the system pulls the chemical formula, hardness, crystal system, and IMA-validated classification directly from Mindat in real time. No manual lookup, no copy-paste, no stale data.

• Developer API - full programmatic access to your collection. A REST API that lets you query your own specimens, cabinets, and wishlist programmatically. Build your own integrations, connect third-party tools, or use C40 as a headless CMS for a personal mineral website. Your data, your code, your rules.

• Advanced, fully customizable field sets per specimen. You decide which fields are visible on a card, on a label, in print, in a public share. Not a fixed six-field form. You can create different field profiles for different collection types or display contexts.

• Virtual cabinets (gabloty). Arrange specimens on virtual shelves the way they sit in your real cabinet, with drag and drop, multiple cabinets, and per-shelf layout. Not a grid view with thumbnails - a spatial representation of your actual storage.

• Wishlist with public sharing. A structured "what I am looking for" list that you can share with dealers and fellow collectors. Filterable, shareable, first-class entity inside your collection system.

• Strict IMA nomenclature with built-in mineral knowledge base. Classes, groups, subclasses, and localities wired into autocomplete and validation.

• Field Mode. Offline drafts (photo + name + location) on mobile, which sync to the cloud when you are back online. Designed for field trips, mineral shows, and remote localities with no signal.

• Print Layout Editor. A Figma-like editor for collection labels and catalog pages, with multiple paper sizes and per-card field selection. Museum-quality PDF labels from the same data you use for online sharing.

• Bulk Excel and CSV import with fuzzy duplicate detection by full inventory ID, name plus location plus size signature, and a skip-or-overwrite dialog.

• Cross-device sync with real-time updates and panel UI preferences stored in the cloud.

• Provenance and sensitivity. Chain of ownership tracking, plus per-field sensitivity controls. Hide exact localities on public shares while keeping them in your private record.

• Multi-language UI - Polish, English, Spanish, Italian. Interface, help center, and printed labels all respect your language.

• Privacy by default. No EXIF leakage from uploaded photos, collector data isolated by Row-Level Security, separate marketplace identity.

• AI assistance - auto-generated specimen descriptions, AI alt text for photos, and SEO-optimized metadata for public shares.

Earthwonders in a nutshell

Earthwonders ("the home of mineral collecting") is a web-based marketplace plus community plus lightweight collection catalog, all in one. The collection manager exists primarily to feed the marketplace and the social layer.

Publicly stated features:

• Free collection management, no caps, no credit card required.

• Per specimen: one main species plus up to three associated species, up to ten photos or videos, drag-to-reorder.

• Provenance with chain of ownership; "historical collection" auto-fill via community data.

• One-link sharing per collection or per specimen. QR codes for single specimens.

• In-app messaging, make or receive offers, live market data from platform sales.

• Auto-save, private by default.

• Export: stated as "Yes" on the site, with no technical details published.

No public information on: PDF or printed labels, offline mode, multi-language UI, native mobile app, AI features, Excel or CSV import, public API, server location, data residency, or RODO posture.

Earthwonders' own 2026 comparison article references MineralDex and NM Collector as "legacy desktop apps". Cabinet No. 40 is not mentioned.

Feature comparison

Pricing

Earthwonders: cataloging is free; selling costs 5% commission plus standard credit card fees. No listing fees, no subscriptions.

Cabinet No. 40: cataloging has a free tier; Kustosz and Kustosz+ unlock Field Mode, larger collections, and advanced features. Marketplace sales are billed separately.

If your only goal is "list and sell stones with the lowest possible friction", Earthwonders' model is simpler. If your goal is "manage a serious collection long-term and occasionally sell", C40's split - collection tool plus optional marketplace - maps better onto how the work actually splits.

Who is it for?

Earthwonders is a strong fit if you want:

• A single place to list specimens for sale to an existing mineral-collecting audience.

• A community layer with messaging, offers, and live market data.

• The lightest possible catalog with zero setup.

Cabinet No. 40 is a strong fit if you want:

• A real collection-management system: customizable field sets, virtual cabinets, wishlist, print labels, offline Field Mode, Excel import.

• OpenMindat API automation that fills mineral data as you type.

• Developer API access to build your own integrations or frontends.

• Strict IMA nomenclature and a built-in knowledge base wired into your catalog.

• EU data residency, per-field privacy controls, no EXIF leakage.

• Multi-language UI for international correspondents and dealers.

• A clean separation between "my private collection" and "what I have for sale".

Many collectors will reasonably end up using both: C40 as the system of record for the collection, Earthwonders (or any marketplace) as one of the channels to sell.

Shared strengths

• Free entry point - both let you start cataloging without paying.

• Provenance taken seriously - both treat chain of ownership as a first-class field.

• Public sharing of specimens via stable links.

• Private by default.

Honest limitations

Cabinet No. 40:

• No in-app buyer-seller messaging on the cataloging side; marketplace flow is separate.

• No live, platform-wide market price data.

• No native iOS or Android app; Field Mode is a web-based offline experience.

Earthwonders:

• Catalog depth is limited to what a marketplace needs - fixed fields, no public information about virtual cabinets, wishlists, printed labels, offline mode, Excel import, multi-language UI, or API.

• No public information about data residency or RODO posture.

• Selling outside the platform is not the product's focus.

Bottom line

Earthwonders is a community marketplace with a catalog. Cabinet No. 40 is a collection-management platform with an optional marketplace. Pick by the job you actually need done.

If you have already outgrown a spreadsheet, want customizable fields, virtual cabinets, a wishlist, printed labels, OpenMindat API automation, developer API access, and offline field work - C40 was built for exactly that. You can try the Collector Panel for free and see if it fits your collection.

Sources

• earthwonders.com (homepage, /about-earthwonders, /mineral-collection-manager, /help-center, blog post "The Best Software for Cataloging a Mineral Collection in 2026")

• cabinetno40.com (Collector Panel, /en/mineral-collection-manager, public changelog and help center)

• Web search across Reddit r/mineralcollecting and Mindat references (no substantive Earthwonders technical reviews found at time of writing)