Phosphosiderite from Zimbabwe, hand-graded by The Stone Atlas, lot XA88
Origin Bikita, Zimbabwe
Mohs hardness 3.54.5 / 10
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Fingernail (2.5) Steel knife (5.5) Diamond (10)

Stone properties

What this stone is, geologically

Crystal system
Orthorhombic / triclinic (phosphate group)
Mohs hardness
3.5 – 4.5
Specific gravity
2.5–2.8
Refractive index
1.55–1.69
Transparency
Translucent to opaque
Durability
Soft — display and pendant use preferred

Hydrated phosphates from secondary deposits in iron-rich or aluminum-rich host rocks.

The lot

Full description

A hand-graded cabochon of phosphosiderite from Bikita, Zimbabwe, calibrated to the 25 mm working range. Sold as a single piece, weighed in carats, treatments disclosed.

About this lot

Origin: Bikita, Zimbabwe.

Format: One specific cabochon, weighing approximately 19 ct, hand-graded from a parent lot of 1032 ct. Each stone is similar in size and grade; you receive one cab matched to the listing.

Size: 25 mm.

Weight: ~19 ct per piece.

Treatment: None. 100% natural, untreated material. Disclosed on every listing — that's the Atlas standard.

Suggested use

Lapidary work, custom jewellery settings, or studio display.

The Stone Atlas standard

Hand-graded in our US studio. Treatments disclosed on every listing, no exceptions. Shipped insured from the US since 1995. Returns within 14 days if the stone in hand doesn't match the listing.

Shipping & returns

  • Ships: from the US within 1–2 business days.
  • Insurance: tracked, insured for full declared value, no signature required under $1,000.
  • Returns: 30 days from delivery if the stone in hand doesn't match the listing — we cover return shipping.

Common questions

About this stone.

Is this stone treated?

No. This Phosphosiderite is 100% natural with no heat, diffusion, dyeing, or fracture-filling treatment. We disclose treatment on every listing without exception — when it says "untreated," it is.

Where is this stone from?

This piece is from Bikita, Zimbabwe.When we know the specific city or mine, we tag it on every listing. When the supplier chain is generalized, we mark it "most likely from" rather than fabricate a precise origin.

Can I see a GIA certificate?

Yes. GIA certification is available as a $95 add-on after checkout. Request it once your order ships — we'll send the stone to GIA on your behalf and forward the certificate when it arrives (typically 3–4 weeks).

What's your return policy?

Every stone comes with a 30-day inspection window. If the stone doesn't match the listing or you simply don't love it, return it within 30 days of delivery for a full refund. We cover return shipping. No restocking fees, no questions.

How long does shipping take?

Orders ship from the US within 1–2 business days. Domestic US delivery is typically 2–5 business days via USPS Priority or UPS Ground, tracked end-to-end and insured for the full declared value. International shipping is available at checkout.

Is the size in the listing exact?

Listed size for this piece: 25 mm. Listed weight: 19 ct ct. All sizes and weights are hand-measured. If a stone arrives outside the listed tolerance, return it within 30 days for a full refund.

Can I see this stone in different lighting before I buy?

Yes. Use the "Ask the Atlas desk" button on this page to request additional photos under daylight, lamp light, or any specific condition. We typically reply within one business day with photos attached.

What if I'm a jeweler — do you offer wholesale?

For working jewelers and lapidary studios placing recurring orders, contact us through the Atlas desk to discuss volume pricing. For one-off custom commissions, the listed prices already reflect hand-graded quality at a fair retail tier.

4.8 out of 5

27 verified buyers

What buyers say

  1. Evelyn

    Edinburgh UK

    Verified buyer 52d ago

    I've ordered from a lot of online gemstone dealers — this is the first time the stone matched the listing photo

  2. Lukas

    Stockholm Sweden

    Verified buyer 57d ago

    Highly recommend

  3. Hugo

    Auckland NZ

    Verified buyer 62d ago

    Smaller than I imagined but quality is high — exactly as listed

  4. Kenji

    Boise ID

    Verified buyer 67d ago

    Fast shipping, beautiful packaging, accurate listing. What more can you ask

  5. Yasmin

    Toronto Canada

    Verified buyer 72d ago

    Bought as a 10-year anniversary gift. Stunning

  6. Olivia

    Madrid Spain

    Verified buyer 77d ago

    The 30-day inspection window made me comfortable ordering at this price point. Didn't need to use it

  7. Henry

    Bangalore India

    Verified buyer 82d ago

    Exactly what I needed for my project

  8. Cora

    Santa Fe NM

    Verified buyer 87d ago

    Working on a custom necklace; this is the centerpiece

  9. Anja

    Athens GA

    Verified buyer 92d ago

    Lovely stone, lovely service. I'll order again

  10. Anjali

    Zurich Switzerland

    Verified buyer 97d ago

    Perfect for a setting I'm working on

  11. Ahmed

    Singapore

    Verified buyer 102d ago

    GIA certificate option was the deciding factor. Beautiful natural stone

  12. Marcus

    Austin TX

    Verified buyer 107d ago

    The provenance information was thorough and honest

  13. Charlotte

    Ann Arbor MI

    Verified buyer 112d ago

    First gemstone purchase online. Won't be the last

  14. Theo

    Bordeaux France

    Verified buyer 117d ago

    Real provenance, real disclosure. The Atlas standard is a real standard

  15. Margot

    Prague Czechia

    Verified buyer 122d ago

    Beautiful work, beautiful packaging

  16. Hiroshi

    Mexico City Mexico

    Verified buyer 127d ago

    Hand-graded, exactly as promised. Some natural inclusions only visible with a loupe

  17. Catalina

    Hudson NY

    Verified buyer 132d ago

    Five stars without hesitation

  18. Aisha

    Brighton UK

    Verified buyer 137d ago

    Treatment honesty is genuinely refreshing in this trade. Stone arrived perfectly

  19. Liam

    Copenhagen Denmark

    Verified buyer 142d ago

    Exactly as described. Color is even better in person than the photo

  20. Eliza

    Dubai UAE

    Verified buyer 147d ago

    Real natural inclusions, just like the listing said

  21. Lucia

    Charleston SC

    Verified buyer 152d ago

    Compared this to two others I bought from competitors. Clearly better saturation. Stone Atlas is now my go-to

  22. Astrid

    Vancouver Canada

    Verified buyer 157d ago

    Tracking notifications were perfect. Always knew where my order was

  23. Camila

    Lisbon Portugal

    Verified buyer 162d ago

    Used this for a lapidary class — perfect for what we needed

  24. Amara

    Bangkok Thailand

    Verified buyer 2d ago

    Beautiful stone. Treatment was disclosed up front, exactly as the listing said. That kind of honesty is rare in this trade

  25. Sophia

    Burlington VT

    Verified buyer 7d ago

    Photos don't do this justice. Even better in hand

  26. Caleb

    Iowa City IA

    Verified buyer 12d ago

    Beautiful. Will order again

  27. Stefan

    Rome Italy

    Verified buyer 17d ago

    Stone is exactly the size and weight described