Scattered precious gemstones — rubies, sapphires, emeralds, diamonds, yellow sapphires and pearls on burgundy velvet

Jewellers Since 1979

Diamond House — Authentic Gemstones and Gemmological Lab

Gems & Lab — hand-picked gemstones, identified before they leave.

A curated catalogue of precious and semi-precious gemstones, diamonds and fine jewellery — sold directly by a three-generation family house in Kolhapur. Every stone is examined in our own gem lab and dispatched with its identification report.

Already have a identification report? Scan the QR or enter the ID below to verify it instantly.

Tamper-proof
QR Verified
Lab Examined
Signed Card
The nine sacred Navratna gemstones — ruby, pearl, red coral, emerald, yellow sapphire, diamond, blue sapphire, hessonite and cat's eye

A Legacy in Stone

Diamond House Gemmological Lab is a professional gemstone authentication house — rooted in Maharashtrian heritage, master craftsmanship, and timeless elegance.

Built on trust and precision, our identification process helps customers, collectors, jewelers, and families verify the authenticity and characteristics of their precious gemstones with confidence.

The Navratna

Nine sacred stones, one trusted house.

Each gemstone hand-picked, examined under our lab, and dispatched with its signed identification report.

Flat-lay of the nine Navratna gemstones arranged in a circle

Gemstones

We don't just identify. We sell, too.

The nine sacred Navratna stones and a curated wider spectrum of semi-precious gems — each hand-picked, personally evaluated, and dispatched with its own authentication identification report.

Explore the Catalog

Services

  • 01

    Natural Gemstone Authentication

    We confirm whether your stone is natural, treated, or synthetic — in plain language.

  • 02

    Diamond Verification

    4Cs report — cut, colour, clarity, carat — for loose and mounted diamonds.

  • 03

    Ruby, Emerald & Sapphire

    Origin opinion and treatment disclosure for the big three coloured stones.

  • 04

    Natural vs Synthetic ID

    Lab-grown vs earth-mined — separated under the microscope, never guessed.

  • 05

    Identification Cards

    A printed visiting-card identification report travels with your stone, forever.

  • 06

    QR Digital Verification

    Scan the QR — your identification report appears here, instantly, anywhere.

  • 07

    Jewelry Stone Evaluation

    Honest, unbiased opinion on stones already set in your family jewellery.

Est. 1979 · Three Generations

A jewellery house built in 1979.
A gem lab built for today.

Diamond House was founded in 1979 by Prakash Kolhapure — Aakanksha's grandfather. Nearly five decades later, the same family — now in its third generation — brings professional gemmology and modern laboratory science to the trust that started it all.

  1. 01

    1979

    Prakash Kolhapure

    Aakanksha's grandfather established Diamond House in Kolhapur — a small jewellery house built on honesty, hand-picked stones, and a handshake.

  2. 02

    Second Generation

    Prasad Kolhapure

    Aakanksha's father carried the trade forward — deepening relationships with mines, cutters, and clients who returned generation after generation.

  3. 03

    Today

    Aakanksha Kolhapure

    Third-generation gemmologist. Trained in modern gemmology and an authenticated member of the gemmological society — pairing heirloom trust with laboratory precision.

Professional Gemmologist Society Member Since 1979 Third Generation

The Identification Report Card

A signed, scannable mark of authenticity.

Every authenticated gemstone receives a visiting-card-sized identification report — onyx front, ivory back, gold corner marks, and a QR code that points to its digital verification on this site. The card travels with the stone; the truth lives in the database.

  • · 3.5″ × 2″ business-card format · printable PDF export
  • · QR links directly to /?cert=ID for instant verification
  • · Generated automatically when admin issues a identification report
No Photo

Scan to
Verify

Diamond House

Gemmological Lab

Gemstone Identification Report

No: DHGL-G-2026-00001Date: Jan 01, 1970
IdentificationNATURAL YELLOW SAPPHIRE
Weight
4.52 ct
Colour
Yellow
Cut
Oval
Measure (mm)
10.12 × 8.05 × 5.42
R.I.
1.760 – 1.768
S.G.
4.00
Market
Pukhraj
Hardness
9

Transparency: Transparent·Origin: Sri Lanka·Treatment: Heated·Pleochroism: Yellow / Pale Yellow·Polariscope: DR·UV Fluor.: Inert·Microscope: Typical silk inclusions, colour zoning present.

Terms & Conditions

  1. This report states the findings of Diamond House Gemmological Lab at the time of examination only.
  2. The report applies only to the gemstone examined and is not a valuation, guarantee, warranty, or proof of ownership.
  3. Any treatment, enhancement, recutting, repolishing, mounting, or alteration after examination may affect the validity of this report.
  4. Results are based on standard gemmological testing methods. Certain characteristics or treatments may not be detectable.
  5. Liability, if any, shall be limited to the fee paid for testing and report issuance.
  6. Authenticity should be verified via QR code. Disputes subject to Kolhapur, MH jurisdiction.

Diamond House Gemmological Lab

607 Krystal Square, Nagala Park, Kolhapur · diamondhouse.in

Diamond House Gemmological Lab

Aakanksha Kolhapure

Professional Gemmologist

The Diamond Grading Report

A full-page report for every diamond.

Each diamond we authenticate is documented in a full A4 grading report covering shape, measurements, carat weight, colour, clarity, cut, polish, symmetry, fluorescence and inscription — finished with a QR code that opens its digital verification.

  • · A4 portrait format · printable PDF export
  • · QR links to /diamond-report/REPORT_NO for instant verification
  • · Generated automatically when admin issues the report
DIAMOND HOUSE GEMMOLOGICAL LAB
607 Krystal Square, Nagala Park, Kolhapur
aakankshakolhapure@yahoo.com
REPORT NO. DHGL-D-2026-00001
DATE: January 01, 1970

NATURAL DIAMOND GRADING REPORT

ISSUED BY
Diamond House Gemmological Lab
PREPARED FOR
Identified AsNatural Diamond
Growth OriginNatural
Shape and Cutting StyleRound Brilliant
Measurements7.30 - 7.35 x 4.46 mm
GRADING RESULTS
Carat Weight1.50 carat
Color GradeG
Clarity GradeVVS2
Cut GradeExcellent
ADDITIONAL GRADING INFORMATION
PolishExcellent
SymmetryExcellent
FluorescenceNone
Inscription(s)DHGL 00001
Comments: Sample diamond grading report.
DIAMOND IMAGE
DIAMOND HOUSE GEMMOLOGICAL LAB
VERIFY ONLINE
SCAN TO VERIFY THIS REPORT
GRADING SCALES
COLOR
DEFGHIJKLMNOPQRSTUVWXYZ
CLARITY
FLIFVVS1VVS2VS1VS2SI1SI2I1I2I3
CUT
EXCELLENTVERY GOODGOODFAIRPOOR
The results documented in this report refer only to the diamond described, examined using techniques and equipment available at Diamond House Gemmological Lab on the date issued. This report is not a guarantee or valuation. See page 2 for clarity characteristics, proportions, signature and terms.
DIAMOND HOUSE GEMMOLOGICAL LAB · PAGE 2
REPORT NO. DHGL-D-2026-00001
CLARITY CHARACTERISTICS & PROPORTIONS
CLARITY PLOT
CROWN VIEW
PAVILION VIEW
NO CLARITY CHARACTERISTICS PLOTTED
SYMBOLS INDICATE TYPE, POSITION & SIZE
PROPORTIONS
57.0%15.0%34.5°50.0%Medium to Slightly Thick · 3.5%43.0%40.8°Lower 75.0%62.3%Culet: None
Diamond House Gemmological Lab
Aakanksha Kolhapure
PROFESSIONAL GEMMOLOGIST
AUTHORIZED GEMMOLOGIST
Diamond House Gemmological Lab
TERMS & CONDITIONS
  1. This report states the findings of Diamond House Gemmological Lab at the time of examination only.
  2. The report applies only to the gemstone or diamond examined and is not a valuation, guarantee, warranty, or proof of ownership.
  3. Identification as Diamond confirms the species only and does not indicate growth origin unless specifically stated.
  4. Growth Origin is reported only when determined. If shown as “Not Determined” or “Not Tested”, no opinion is expressed regarding natural or laboratory-grown origin.
  5. Any treatment, enhancement, recutting, repolishing, mounting, damage, or alteration after examination may affect the validity of this report.
  6. Results are based on standard gemmological testing methods available at the time of examination. Certain characteristics or treatments may not be detectable.
  7. Liability, if any, shall be limited to the fee paid for testing and report issuance.
  8. Report authenticity should be verified through the QR code. All disputes shall be subject to the jurisdiction of Kolhapur, Maharashtra, India.
DIAMOND HOUSE GEMMOLOGICAL LAB · KOLHAPUR · diamondhouse.in

How it works

From your hand to a verified identification report — in four simple steps.

No jargon, no guesswork. Here is exactly what happens when you bring a stone to us.

  1. 01

    Bring your stone

    Drop it off at our Kolhapur atelier, or book a private viewing.

  2. 02

    We examine

    Microscope, refractometer, polariscope — the full gemmological work-up.

  3. 03

    Receive your card

    A signed identification report card with a unique ID and a scannable QR code.

  4. 04

    Verify anytime

    Anyone, anywhere — scan the QR to confirm authenticity on this site.

Smartphone scanning the QR code on a Diamond House identification card

Identification Report Verification

Verify Your Identification Report

Scan Lookup Verified

Each gemstone identification report issued by Diamond House Gemmological Lab — 607 Krystal Square, Nagala Park, Kolhapur — carries a unique Identification Report ID and QR verification system for secure validation. Enter your Identification Report ID below to access the gemstone identification report.

Try the sample ID AKGL-2026-00421

Signed By

Aakanksha Kolhapure

Professional Gemmologist

In Their Words

Trusted across generations

  • We've been buying gold from Diamond House since my mother's wedding. When Aakanksha tested my grandmother's emerald and gave us a proper identification report, it felt like the family had finally caught up with the times — without losing what made them special.

    Priya Deshmukh

    Customer · Kolhapur

  • I went to three jewellers in Pune before someone told me to drive to Kolhapur. Prasad sir picked out a pair of natural blue sapphires within ten minutes. The identification report, the photos, the price — everything was upfront. Worth the trip.

    Rohit Joshi

    Customer · Pune

  • Got our engagement ring made here with a solitaire we chose ourselves. They walked us through every C, showed inclusions under the microscope, and didn't push us towards anything. Quiet confidence — that's the only way to describe it.

    Sneha & Amey

    Couple · Kolhapur

Visit & Connect

Three showrooms. One trusted house.

Walk into any of our locations across Kolhapur and Pune, or message us first and we'll have the stone ready for you.

  • Kolhapur — Showroom

    230B, Jotiba Road

    Kolhapur 416012

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  • Kolhapur — Lab

    607 Krystal Square

    Nagala Park, Kolhapur

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  • Pune — Branch

    3, Radha Krishna Apartment

    Bibwewadi-Kondhwa Road, Pune 411037

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