📌 Grading Overview (How We Judge Tree Agate)

Tree agate is an opaque chalcedony with green, branch‑like inclusions. There’s no universal laboratory grade (like “D color” in diamonds), so the market relies on a combination of visual merits and craftsmanship. In practice, top material shows: clean white matrix, crisp dendritic branching, balanced composition, high contrast, and an even, glassy polish.

🧭 Visual Grading Rubric 

Use this as a practical guide. Names (Premium / Select / Standard / Commercial) are descriptive, not absolute — dealers vary. Weights help when scoring mixed lots.

Scoring idea: rate 1–5 on each criterion, multiply by the weight, total to 100. Premium ~85–100, Select ~70–84, Standard ~55–69, Commercial <55.

🪚 Cut, Polish & Craft (Where Grade Meets Skill)

• Orientation: Rotate slabs so the densest branching sits on a clean white field. Avoid chopping a beautiful fork right at the bezel line.
• Dome height: Low–medium domes preserve readability. Very high domes can distort patterns in opaque material.
• Edge integrity: A slight back bevel helps prevent flaking where inclusion density is high.
• Polish recipe: Finish with fine diamond or cerium; inspect for undercut glare around inclusion clusters.
• Pairs & sets: Book‑matched slices for earrings/bracelets command premiums — symmetry sells the “forest.”

💰 Value Drivers (What Actually Moves Price)

🧪 Treatments & Disclosure

• Dyeing (common): Used to intensify greens. Clues: neon‑even color, pooling in cracks, strong UV response. Dyed pieces should be priced accordingly.
• Wax/resin surface finish: Sometimes used to close micro‑pits. Acceptable as a finish; disclose if it materially affects appearance.
• Stabilization: Uncommon but possible in porous sections. Ask for disclosure; stabilization doesn’t “upgrade” grade, it just improves usability.

🌎 Localities Overview

Tree agate is widely distributed. In the trade, India has long been a major source and cutting hub, with additional material reported from Brazil, Madagascar, and parts of the United States. Local geology (host rock, fluid chemistry, weathering history) nudges the look toward certain tendencies — cleaner whites here, darker accents there — but every lot is unique, and cutting orientation can change the story dramatically.

🗺️ Locality Tendencies (General, Not Absolute)

Remember: locality informs expectation, not grade. Grade is on the stone — contrast, branching, integrity, and finish.

🌱 Sourcing & Ethics

• Origin transparency: Ask suppliers whether “India/Brazil/Madagascar/USA” refers to mining origin, cutting origin, or both.
• Treatment disclosure: Label dyed material clearly. It pleases customers and protects your brand.
• Working conditions: Favor suppliers who can speak to safe cutting and fair labor in their workshops.
• Waste & packaging: Encourage water recycling in cutting and use recyclable or minimal retail packaging.

🧾 Buying Checklist (Fast Pass)

• Matrix: Is the white clean and even? Any muddy stains or pits?
• Branches: Do you see tapered forks and side twigs (natural) or blobs (meh)?
• Contrast & composition: Does the “grove” read clearly with pleasing negative space?
• Integrity: Any face‑reaching fractures or edge chips?
• Polish: Even, glassy finish without orange‑peel or wheel lines?
• Size & shape: Will the pattern survive the bezel/prongs? For small pieces, prefer vein‑laced material.
• Pairs/sets: For earrings/strands, are patterns consistent across the lot?
• Disclosure: Natural or dyed? Any surface wax/resin? Note it on the tag.
• Locality: If origin matters, request it in writing (mine/region or “cut in ___”).

❓ FAQ

✨ The Takeaway

Grading tree agate is equal parts art and due diligence. Start with the stone: clean matrix, crisp branching, balanced composition, solid integrity, and a fine polish. Use locality as a helpful hint, not a verdict, and keep treatment disclosure front‑and‑center. Do that consistently and every piece feels like walking past a tiny forest — no hiking boots required. 🌲