Operator: Sho Kitano
Business address: Hiratsuka, Kanagawa, Japan
Antique dealer license: Kanagawa Prefectural Public Safety Commission No. 452680013478
Contact: papurika2016@gmail.com

The Service collects and uses the following information for the following purposes.

• Analytics data (Google Analytics 4): page views, session duration, referrers, device type, and approximate geographic region (city level). Used to understand usage and improve the Service. IP addresses are anonymised on Google's side.
• Contact and photo-contribution form submissions: email address, handle, stone name, locality, planned photo type, comments. Used to reply and to coordinate inclusion of contributed photos in the gem dictionary.
• Device-local data (localStorage): photos and notes saved to "My Dictionary", theme preference (light/dark), expanded-glossary state, and similar UI state. All such data is stored only in your browser on your device, and is never transmitted to our servers.
• Service Worker cache (PWA): HTML, images, and JavaScript files are cached on your device for offline use and faster display. This cache, too, stays on your device.

The Service uses the following third-party providers.

• Google Analytics 4 (Google LLC) — analytics. Uses cookies and similar technologies to measure usage. See the Google Privacy Policy for details. To opt out of cookies, use your browser settings or the Google Analytics opt-out browser add-on.
• Formspree (Formspree, Inc.) — destination for contact and photo-contribution form submissions. Submitted content is routed through Formspree's servers in the United States to our email address. See the Formspree Privacy Policy.

Other than the above, we do not share personal information with third parties without your consent, except as required by applicable law.

Information submitted through the photo contribution form is used only to coordinate inclusion of those photos in the dictionary.

• Your email address and handle are used solely for replying about the contribution and, where appropriate, for crediting the photographer.
• EXIF metadata (including GPS coordinates) is stripped from contributed photos before publication.
• You may request takedown of your contributed photos at any time.
• We also accept factual-accuracy concerns regarding already-published third-party photos.

To improve usability, the Service stores the following items in your browser's localStorage. All such data stays on your device and is not transmitted to us or to any third party.

• My Dictionary: per-stone photos (stored locally as Data URLs) and timestamps.
• Display preferences: light/dark theme selection.
• Glossary state: which glossary entries you have expanded.

Clearing site data from your browser settings will remove this information.

The Service uses cookies for Google Analytics. Cookies can be disabled through your browser settings. The core features of the Service (identification flow, dictionary browsing, PDF export) remain usable with cookies disabled.

Personal information received through the contact and photo-contribution forms is stored within an email environment under the operator's control, protected by strong passwords and two-factor authentication to prevent third-party disclosure.

To request disclosure, correction, or deletion of personal information about yourself, please email the address listed under "Operator" above. After verifying your identity, we will respond promptly within reasonable limits.

For data submitted via the photo-contribution form, we also accept "withdraw before publication" requests.

The Service does not knowingly collect information from minors (under 18). If you believe a minor has submitted information without parental consent, please contact us at the address above, and we will verify and delete that information.

This policy may be revised in response to legal changes or changes to the Service. Updates will be posted on this page, and the "last updated" date will be revised accordingly.