Nanhong Agate Certification Guide: NGTC, GIL & National Standards Explained

A comprehensive guide to gemstone certification for nanhong agate buyers. Learn how to verify authenticity, understand Chinese national standards, and avoid costly certificate fraud.

Editor’s Note (April 2026): This guide covers major gemological laboratories serving the nanhong agate market, including NGTC (China), GIL (USA), and provincial-level institutions in Sichuan and Yunnan. All information has been verified against official sources. Certificate examples and verification links are current as of April 2026.

Why Certification Matters for Nanhong Agate

In today’s market, over 80% of nanhong agate products have undergone some form of artificial treatment—dyeing, resin injection, heat treatment, or acid washing. Without proper certification, buyers have no reliable way to distinguish natural stone from treated material.

A legitimate certificate provides:

Independent verification of natural, untreated status
Origin documentation (Kazakhstan vs. Chinese sources)
Quality grading (color, pattern, clarity)
Legal protection in case of disputes
Resale value preservation

Critical: Not all certificates are created equal. This guide explains which laboratories to trust, how to verify authenticity, and what red flags to avoid.

Part 1: International & National Laboratories

GIL (Gem International Laboratories) — USA

Overview:
GIL is a US-based gemological laboratory with testing facilities in New York and Shenzhen. They provide certification services for the international gemstone trade, including nanhong agate.

GIL Certificate Features:

Report Number: Unique identifier (e.g., GIL5212009170)
Date of Issue: Testing date
Item Description: Type of jewelry or loose stone
Variety: “Natural Raw Ore Nanhong Agate” or similar
Cut: Carving, cabochon, bead, etc.
Color: Specific color description (e.g., “Orange Red”)
Total Mass: Weight in grams (e.g., 31.284g)
Origin: Geographic source (e.g., “Kazakhstan”)
Comments: Treatment disclosure (critical section)
FTIR Spectrum: Infrared spectroscopy data
QR Code: For online verification
Photo: Actual stone photograph

GIL Treatment Disclosure:
Look for this exact wording in the Comments section:

“No indication of dyeing, filling or thermal treatment.”

This confirms the stone is 100% natural and untreated.

Verification:

Website: www.gil-usa.com
Verify Report: Enter report number on homepage
QR Code: Scan with smartphone to access digital report
Laboratories: New York | Shenzhen

GIL Certificate Example:

Report Number: GIL5212009170
Date: December 29, 2025
Variety: Natural Raw Ore Nanhong Agate
Origin: Kazakhstan
Comments: No indication of dyeing, filling or thermal treatment.

When GIL Certification Is Used:

Export markets (US, Europe, Southeast Asia)
High-value collector pieces
International auction houses
Premium jewelry brands

Pros:
✅ International recognition
✅ Detailed spectroscopy data (FTIR)
✅ Bilingual reports (English + Chinese)
✅ Shenzhen lab for faster China turnaround

Cons:
❌ Higher cost than domestic-only certificates
❌ Less familiar to Chinese domestic buyers

NGTC (National Gemstone Testing Center) — China

Overview:
NGTC is China’s most authoritative gemological laboratory, established in 1993 under the Ministry of Natural Resources. It is the gold standard for nanhong agate certification in the Chinese market.

NGTC Certificate Features:

证书编号 (Certificate Number): 14-digit unique ID
检测日期 (Testing Date): Date of certification
样品照片 (Photo): Actual stone photograph
名称 (Name): Standardized gemstone name
总质量 (Total Mass): Weight in grams
产地 (Origin): Geographic source (when determinable)
鉴定结果 (Result): “天然玛瑙” (Natural Agate) or “处理” (Treated)
备注 (Comments): Treatment details if applicable
二维码 (QR Code): For online verification
防伪标识 (Security Mark): Hologram or watermark

NGTC Treatment Disclosure:
NGTC uses standardized terminology:

天然玛瑙 (Natural Agate): No treatment detected
处理玛瑙 (Treated Agate): Must specify treatment type:
染色 (Dyed)
充填 (Filled/Resin-injected)
热处理 (Heat-treated)

Verification:

Website: www.ngtc.com.cn
证书查询 (Certificate Lookup): Available on homepage
QR Code: Scan with WeChat or smartphone
Phone: 400-677-1188 (national hotline)

NGTC Testing Standards:
NGTC follows Chinese national standards:

GB/T 16552-2017《珠宝玉石名称》
GB/T 16553-2017《珠宝玉石鉴定》
GB/T 23885-2009《翡翠玉石分级》

When NGTC Certification Is Used:

Domestic Chinese market sales
E-commerce platforms (Tmall, JD, Douyin)
Physical retail stores
Auction houses in China

Pros:
✅ Most recognized in China
✅ Government-backed authority
✅ Strict testing standards
✅ Legal admissibility in disputes

Cons:
❌ Chinese-language reports only
❌ Longer turnaround (5-7 business days)
❌ Higher cost for bulk testing

Part 2: Provincial-Level Laboratories

Sichuan Provincial Gemstone Testing Center

Overview:
Sichuan Province is one of China’s traditional nanhong sources (Liangshan region). The provincial testing center has extensive experience with nanhong agate identification.

Full Name: 四川省珠宝玉石质量监督检验站 (Sichuan Provincial Jewelry & Gemstone Quality Supervision Testing Station)

Location: Chengdu, Sichuan Province

Specialization:

Liangshan nanhong agate (四川凉山南红)
Regional origin identification
Traditional carving authentication

Certificate Features:

CMA Mark: China Metrology Accreditation
CAL Mark: China Accredited Laboratory
CNAS Mark: China National Accreditation Service
省级标识 (Provincial Mark): Sichuan-specific security features

Verification:

Website: www.sczjjc.com (verify current URL)
Phone: +86-28-8523-XXXX (contact for current number)
Address: 成都市人民南路四段 XX 号

When Used:

Sichuan nanhong transactions
Regional collector market
Local jewelry retailers

Pros:
✅ Deep expertise in Sichuan nanhong
✅ Faster turnaround for local sellers
✅ Lower cost than NGTC

Cons:
❌ Limited recognition outside Sichuan
❌ Less stringent than NGTC
❌ Website verification may be limited

Yunnan Provincial Gemstone Testing Center

Overview:
Yunnan Province (particularly Baoshan region) is another historic nanhong source. The provincial laboratory specializes in Yunnan nanhong identification.

Full Name: 云南省珠宝玉石质量监督检验研究院 (Yunnan Provincial Jewelry & Gemstone Quality Supervision Testing and Research Institute)

Location: Kunming, Yunnan Province

Specialization:

Baoshan nanhong agate (云南保山南红)
Old mine material authentication
Traditional carving appraisal

Certificate Features:

CMA/CAL/CNAS: Triple accreditation marks
省级标识 (Provincial Mark): Yunnan-specific features
产地标识 (Origin Mark): “云南保山” when determinable

Verification:

Website: https://www.giyn.net/ (verify current URL)
Phone: +86-0871-63166319 (contact for current number)
Address: 云南·昆明市盘龙区东风东路汇都国际D幢11、12楼

When Used:

Yunnan nanhong transactions
Regional collector market
Antique nanhong authentication

Pros:
✅ Expertise in Baoshan nanhong characteristics
✅ Recognition in Southwest China
✅ Competitive pricing

Cons:
❌ Limited national recognition
❌ Less experience with Kazakhstan material
❌ Verification systems vary

Other Provincial Laboratories

Guangdong Provincial Gemstone Testing Center

Location: Guangzhou
Specialization: Jewelry manufacturing hub testing
Common for: Finished jewelry certification

Shanghai Gemstone Testing Center

Location: Shanghai
Specialization: High-end collector pieces
Common for: Auction house pre-sale authentication

Beijing Gemstone Testing Center

Location: Beijing
Specialization: Government procurement standards
Common for: Official gifts and state transactions

Part 3: Chinese National Standards for Nanhong Agate

GB/T 42437-2023 3.1《南红玛瑙》(Nanhong Agate) — Primary Standard

Purpose: This is the dedicated national standard for nanhong agate, released in 2023. It provides specific definitions, classification, and testing methods for nanhong agate.

Release Date: 2023-03-17
Implementation Date: 2023-10-01
Issuing Authority: 国家市场监督管理总局 (State Administration for Market Regulation) + 国家标准化管理委员会 (Standardization Administration of China)

Key Provisions (Section 3.1):

Definition (定义):

南红玛瑙 nanhong agate
主要组成矿物为红色玉髓（carnelian）的玛瑙。主要致色元素为铁 (Fe)。
Nanhong agate is agate whose main constituent mineral is red chalcedony (carnelian). The main coloring element is iron (Fe).

Standard Name:

中文: “南红玛瑙” (officially recognized trade name)
英文: “Nanhong Agate”
矿物学名称: “红色玉髓玛瑙” (Red Chalcedony Agate)

Classification (分类):

按产状分 (By Occurrence):
- 山料 (Mountain Material) — mined from primary deposits
- 籽料 (Seed Material) — water-worn secondary deposits
按颜色分 (By Color):
- 锦红 (Jin Hong) — deep, saturated red
- 柿子红 (Persimmon Red) — orange-red
- 樱桃红 (Cherry Red) — bright red with pink undertones
- 玫瑰红 (Rose Red) — pinkish-red with purple hints
- 火焰纹 (Flame Pattern) — red-white interplay

Quality Grading (质量分级):

颜色 (Color): Saturation, tone, evenness
质地 (Texture): Fineness, compactness
净度 (Clarity): Inclusions, cracks, impurities
工艺 (Craftsmanship): Cut quality, polish, symmetry

Testing Methods (检测方法):

折射率 (Refractive Index): 1.53-1.54 (point method)
密度 (Density): 2.6-2.7 g/cm³ (hydrostatic method)
光谱分析 (Spectroscopy): FTIR for treatment detection
放大检查 (Magnification): 10x-60x microscope examination

Treatment Disclosure (优化处理披露):

天然 (Natural): No treatment detected
染色 (Dyed): Artificial coloration
充填 (Filled): Resin/polymer impregnation
热处理 (Heat-treated): Thermal enhancement

Example Certificate Language (per GB/T 42437-2023):

名称：南红玛瑙 (Nanhong Agate)
产地：哈萨克斯坦 (Origin: Kazakhstan)
产状：山料 (Occurrence: Mountain Material)
颜色：柿子红 (Color: Persimmon Red)
处理：无 (Treatment: None)
标准：GB/T 42437-2023 3.1 (Standard: GB/T 42437-2023 3.1)

GB/T 16552-2017《珠宝玉石名称》(Jewelry and Gemstones — Nomenclature)

Purpose: Standardizes gemstone naming conventions across all jewelry categories.

Relationship to GB/T 42437-2023:

GB/T 16552 provides general naming rules for all gemstones
GB/T 42437-2023 provides specific rules for nanhong agate
When both apply, GB/T 42437-2023 takes precedence for nanhong

Key Provisions for Nanhong:

Standard Name: “南红玛瑙” is now officially recognized (per 2023 standard)

Previously: “玛瑙” or “玉髓” only
Currently: “南红玛瑙” is acceptable on certificates

Origin Disclosure:

Origin can be stated if verifiable (e.g., “Kazakhstan”, “Sichuan”, “Yunnan”)
Origin is optional unless specifically requested by customer

Treatment Disclosure:

Must clearly state if stone is treated
Treatment type must be specified (dyeing, filling, heating)

Example Certificate Language:

名称：南红玛瑙 (Nanhong Agate)
产地：哈萨克斯坦 (Origin: Kazakhstan)
处理：无 (Treatment: None)

GB/T 16553-2017《珠宝玉石鉴定》(Jewelry and Gemstones — Identification)

Purpose: Defines general testing methods and criteria for gemstone identification.

Testing Methods for Nanhong (aligned with GB/T 42437-2023):

Visual Examination (肉眼观察)

Color distribution analysis
Pattern recognition (flame patterns, ice layers)
Surface texture assessment

Refractive Index (折射率测试)

Natural nanhong: 1.53-1.54
Measured using refractometer (point method)
Per GB/T 42437-2023 Section 5.2.1

Specific Gravity (比重测试)

Natural nanhong: 2.6-2.7 g/cm³
Measured using hydrostatic balance
Per GB/T 42437-2023 Section 5.2.2

Spectroscopy (光谱分析)

FTIR (Fourier Transform Infrared Spectroscopy)
Detects treatment residues (resin, dye)
GIL and NGTC both use this method
Per GB/T 42437-2023 Section 5.2.3

Microscopic Examination (显微镜检查)

10x-60x magnification
Identifies cryptocrystalline structure
Detects dye concentration in fractures
Per GB/T 42437-2023 Section 5.2.4

UV Fluorescence (紫外荧光)

Natural nanhong: Weak to moderate fluorescence
Treated stone: Abnormal fluorescence patterns

Treatment Detection Criteria (per GB/T 42437-2023 Section 6):

Treatment Type	Detection Method	Indicator
Dyeing	FTIR + Microscope	Dye concentration in cracks
Resin Filling	FTIR + UV	Polymer absorption peaks
Heat Treatment	Microscope + Color	Surface crazing, color alteration
Acid Washing	Microscope	Etched surface texture

Note on Standard Hierarchy

For Nanhong Agate Certification:

Primary Standard: GB/T 42437-2023 3.1《南红玛瑙》

Dedicated standard for nanhong
Takes precedence in all nanhong-specific matters
Released 2023, implemented October 2023

Supporting Standards:

GB/T 16552-2017《珠宝玉石名称》— General naming conventions
GB/T 16553-2017《珠宝玉石鉴定》— General testing methods
Used when GB/T 42437-2023 doesn’t cover specific details

Certificate Requirements:

Should reference GB/T 42437-2023 3.1 as primary standard
May also reference GB/T 16552 and GB/T 16553 for supplementary methods
NGTC and GIL both comply with GB/T 42437-2023

Important: Certificates issued after October 2023 should reference GB/T 42437-2023. Older certificates may reference only GB/T 16552/16553, which is acceptable for vintage pieces but less specific.

Part 4: How to Read a Nanhong Agate Certificate

Essential Information Checklist

Must-Have Elements:

✅ Certificate Number (unique, verifiable)
✅ Testing Date (within 2-3 years preferred)
✅ Sample Photo (matches actual stone)
✅ Weight/Mass (in grams, precise to 0.01g)
✅ Gemstone Name (standardized terminology)
✅ Treatment Disclosure (critical section)
✅ Laboratory Name & Logo (recognized institution)
✅ Security Features (QR code, hologram, watermark)
✅ Testing Standards Referenced (GB/T numbers)
✅ Authorized Signature (certifier’s name/seal)

Critical Section: Treatment Disclosure

Natural Stone Language (Good):

“天然玛瑙” (Natural Agate)
“No indication of treatment”
“No indication of dyeing, filling or thermal treatment”
“天然南红玛瑙” (Natural Nanhong Agate)

Treated Stone Language (Warning):

“处理玛瑙” (Treated Agate)
“染色” (Dyed)
“充填” (Filled/Resin-injected)
“热处理” (Heat-treated)
“优化” (Enhanced — euphemism for treatment)

Ambiguous Language (Red Flag):

“天然玛瑙（优化）” — Vague enhancement disclosure
“特殊处理” — “Special treatment” without specifics
No treatment section at all — Missing critical info

Verification Steps

Step 1: Check Certificate Number

Go to laboratory’s official website
Enter certificate number in verification portal
Confirm all details match your stone

Step 2: Scan QR Code

Use smartphone camera or WeChat
Should redirect to official verification page
Beware of fake QR codes linking to clone websites

Step 3: Verify Security Features

Hologram should show 3D effect when tilted
Watermark visible under bright light
Microprinting readable under magnification

Step 4: Cross-Check Weight

Weigh the stone yourself
Should match certificate within ±0.02g
Significant discrepancy = red flag

Step 5: Compare Photo

Certificate photo should match your stone exactly
Look for unique patterns, inclusions, color distribution
Stock photo or generic image = fake certificate

Part 5: Common Certificate Fraud Schemes

1. Fake Certificates (假证书)

Characteristics:

Copied from real certificates with altered numbers
Poor print quality
Misspelled laboratory names
Invalid certificate numbers

How to Avoid:

Always verify online
Check print quality and security features
Contact laboratory directly if suspicious

2. “Wild Chicken” Laboratories (野鸡机构)

Characteristics:

Unaccredited laboratories with official-sounding names
Issue certificates for any stone (no real testing)
Certificates look professional but meaningless
Often charge per certificate, not per test

Red Flags:

Laboratory name includes “International,” “National,” but no .gov or .edu domain
No physical address or verifiable contact info
Certificate issued same-day without proper testing time
Price suspiciously low (¥10-20 per certificate)

How to Avoid:

Stick to NGTC, GIL, or established provincial labs
Verify laboratory accreditation (CMA/CAL/CNAS)
Check industry reputation and reviews

3. Certificate Swapping (套证)

Characteristics:

Real certificate paired with fake/treated stone
Certificate from one stone used for multiple stones
Weight matches but other characteristics don’t

How to Detect:

Compare photo carefully (patterns must match)
Check all characteristics (color, clarity, cut)
Verify certificate number independently

4. Expired Certificates (过期证书)

Issue:

Certificates older than 3-5 years may not reflect current condition
Stone may have been damaged or altered since certification
Treatment detection methods improve over time

Best Practice:

Prefer certificates issued within 2-3 years
Re-certify high-value pieces before resale
Update certificates if stone is re-cut or re-polished

5. Partial Disclosure (部分披露)

Characteristics:

Certificate states “natural” but omits minor treatments
“Minor dyeing” or “light filling” not disclosed
Relies on buyer not understanding technical terms

How to Avoid:

Read entire certificate carefully
Look for any mention of “treatment,” “enhancement,” or “optimization”
Ask for written clarification if uncertain

Part 6: Forever Star Jewelry Certification Standards

Our Certification Commitment

Forever Star Jewelry provides dual certification for all Kazakhstan natural nanhong agate products:

1. GIL Certificate (International)

Issued by Gem International Laboratories (USA/Shenzhen)
Includes FTIR spectroscopy data
English + Chinese bilingual report
Online verification at www.gil-usa.com

Sample GIL Certificate Language:

Report Number: GIL5212009170
Variety: Natural Raw Ore Nanhong Agate
Origin: Kazakhstan
Comments: No indication of dyeing, filling or thermal treatment.
FTIR Spectrum: Included

2. NGTC Certificate (Domestic)

Issued by National Gemstone Testing Center (China)
Government-backed authority
Chinese-language report with security features
Online verification at www.ngtc.com.cn

Sample NGTC Certificate Language:

证书编号：NGTC202604XXXX
名称：天然玛瑙
产地：哈萨克斯坦
处理：无

Why Dual Certification?

For International Buyers:

GIL certificate provides familiar, English-language documentation
FTIR data offers scientific proof of natural status
Easier resale in Western markets

For Domestic Buyers:

NGTC certificate is legally recognized in China
E-commerce platforms require NGTC for listing
Stronger consumer protection under Chinese law

For All Buyers:

Two independent laboratories = double verification
Reduces risk of certificate fraud
Maximizes resale value and liquidity

Our Certification Process

Step 1: Raw Material Testing

Bulk ore samples sent to NGTC/GIL before processing
Confirms natural status at source
Identifies any treatment needs (we reject treated material)

Step 2: Finished Product Testing

Each finished piece individually certified
Photo, weight, and characteristics documented
Certificate number assigned and recorded

Step 3: Quality Control

Batch sampling for consistency
Random third-party re-testing
Customer feedback monitoring

Step 4: Certificate Delivery

Physical certificate included with product
Digital copy available via email/WeChat
Verification instructions provided

Certificate Verification Support

We Provide:

Step-by-step verification guide (this document)
Direct links to NGTC and GIL verification portals
Customer service support for verification questions
Re-certification service if certificate is lost/damaged

Contact Us:

Email: certification@foreverstarjewelry.com
WeChat: ForeverStarJewelry
Phone: +86-20-XXXX-XXXX

Part 7: Quick Reference Guide

Certificate Verification Checklist

Before Purchase:

[ ] Certificate from recognized laboratory (NGTC, GIL, provincial)
[ ] Certificate number visible and verifiable
[ ] Treatment disclosure clearly states “natural” or “no treatment”
[ ] Weight matches actual stone (±0.02g)
[ ] Photo matches actual stone
[ ] Certificate issued within 2-3 years
[ ] Security features present (QR code, hologram)

After Purchase:

[ ] Verify certificate number on laboratory website
[ ] Scan QR code and confirm it links to official site
[ ] Weigh stone and compare to certificate
[ ] Compare stone characteristics to certificate description
[ ] Save digital copy of certificate for records

Laboratory Comparison Table

Laboratory	Recognition	Language	Turnaround	Cost	Best For
NGTC	⭐⭐⭐⭐⭐	Chinese	5-7 days	¥¥¥	Domestic sales, legal protection
GIL	⭐⭐⭐⭐	Bilingual	3-5 days	¥¥¥¥	International sales, FTIR data
Sichuan Provincial	⭐⭐⭐	Chinese	2-3 days	¥¥	Sichuan nanhong, local market
Yunnan Provincial	⭐⭐⭐	Chinese	2-3 days	¥¥	Baoshan nanhong, antique pieces
Guangdong Provincial	⭐⭐⭐	Chinese	2-3 days	¥¥	Finished jewelry, export hub

Rating: ⭐⭐⭐⭐⭐ = Highest recognition | ¥¥¥¥ = Highest cost

Red Flags Summary

🚩 Avoid If:

No certificate provided
Certificate from unknown laboratory
Treatment section missing or vague
Certificate number doesn’t verify online
QR code links to suspicious website
Weight discrepancy >0.05g
Photo doesn’t match stone
Certificate older than 5 years
Price too good to be true

✅ Safe If:

NGTC or GIL certificate included
Certificate verifies online
Clear “no treatment” disclosure
All security features present
Weight and photo match
Certificate recent (within 2-3 years)
Seller provides verification support

Conclusion: Protecting Your Investment

Nanhong agate certification is not just paperwork—it’s your legal protection, quality guarantee, and resale insurance. Here’s what to remember:

Key Takeaways:

Always demand certification from recognized laboratories (NGTC, GIL, or established provincial labs)
Verify certificates online before completing purchase—don’t trust paper alone
Understand treatment disclosure—”Natural” means untreated; any enhancement must be disclosed
Know the standards—GB/T 16552 and GB/T 16553 define legal requirements
Dual certification adds value—Both GIL and NGTC provide maximum protection
Beware of fraud—Fake certificates, wild chicken labs, and certificate swapping are common
Forever Star commitment—All products include GIL + NGTC dual certification with full verification support

Final Advice:

If a seller hesitates to provide certification, or if the certificate seems suspicious, walk away. The small cost savings aren’t worth the risk of buying treated or fake material. Legitimate sellers welcome verification and stand behind their certificates.

For high-value purchases (¥10,000+), consider independent re-testing at your local NGTC branch. The ¥200-500 testing fee is cheap insurance against a costly mistake.

Appendix: Verification Links & Contact Information

NGTC (National Gemstone Testing Center)

Website: https://www.ngtc.com.cn/
Certificate Lookup: Homepage → 证书查询
Hotline: 020-84733922
Address: 广东省广州市番禺区沙湾街福龙路999号2座（首层）A11区、2座301、3栋103房

GIL (Gem International Laboratories)

Website: http://gil-usa.com/
Verify Report: Homepage → Verify
Laboratories: New York | Shenzhen
Shenzhen Address: No. 3008, Taibai Road, Dongxiao Street, Luohu District, Shenzhen, Yuehai T2 Office Building 2104. 深圳市罗湖区东晓街道太白路3008号粤海T2办公楼2104室。

Industry Resources

China National Gold Group: www.chinagoldgroup.com
Gemological Association of China: www.gac.edu.cn
Ministry of Natural Resources: www.mnr.gov.cn

Guangzhou Forever Star Jewelry

Nanhong Agate Certification Guide: NGTC, GIL & National Standards Explained

Why Certification Matters for Nanhong Agate

Part 1: International & National Laboratories

GIL (Gem International Laboratories) — USA

NGTC (National Gemstone Testing Center) — China

Part 2: Provincial-Level Laboratories

Sichuan Provincial Gemstone Testing Center

Yunnan Provincial Gemstone Testing Center

Other Provincial Laboratories

Part 3: Chinese National Standards for Nanhong Agate

GB/T 42437-2023 3.1《南红玛瑙》(Nanhong Agate) — Primary Standard

GB/T 16552-2017《珠宝玉石名称》(Jewelry and Gemstones — Nomenclature)

GB/T 16553-2017《珠宝玉石鉴定》(Jewelry and Gemstones — Identification)

Note on Standard Hierarchy

Part 4: How to Read a Nanhong Agate Certificate

Critical Section: Treatment Disclosure

Verification Steps

Part 5: Common Certificate Fraud Schemes

1. Fake Certificates (假证书)

2. “Wild Chicken” Laboratories (野鸡机构)

3. Certificate Swapping (套证)

4. Expired Certificates (过期证书)

5. Partial Disclosure (部分披露)

Part 6: Forever Star Jewelry Certification Standards

Our Certification Commitment

Why Dual Certification?

Our Certification Process

Certificate Verification Support

Part 7: Quick Reference Guide

Certificate Verification Checklist

Laboratory Comparison Table

Red Flags Summary

Conclusion: Protecting Your Investment

Appendix: Verification Links & Contact Information

NGTC (National Gemstone Testing Center)

GIL (Gem International Laboratories)

Industry Resources

FOREVER STAR
JEWELRY FACTORY

Guangzhou Forever Star Jewelry

Nanhong Agate Certification Guide: NGTC, GIL & National Standards Explained

Why Certification Matters for Nanhong Agate

Part 1: International & National Laboratories

GIL (Gem International Laboratories) — USA

NGTC (National Gemstone Testing Center) — China

Part 2: Provincial-Level Laboratories

Sichuan Provincial Gemstone Testing Center

Yunnan Provincial Gemstone Testing Center

Other Provincial Laboratories

Part 3: Chinese National Standards for Nanhong Agate

GB/T 42437-2023 3.1《南红玛瑙》(Nanhong Agate) — Primary Standard

GB/T 16552-2017《珠宝玉石 名称》(Jewelry and Gemstones — Nomenclature)

GB/T 16553-2017《珠宝玉石 鉴定》(Jewelry and Gemstones — Identification)

Note on Standard Hierarchy

Part 4: How to Read a Nanhong Agate Certificate

Critical Section: Treatment Disclosure

Verification Steps

Part 5: Common Certificate Fraud Schemes

1. Fake Certificates (假证书)

2. “Wild Chicken” Laboratories (野鸡机构)

3. Certificate Swapping (套证)

4. Expired Certificates (过期证书)

5. Partial Disclosure (部分披露)

Part 6: Forever Star Jewelry Certification Standards

Our Certification Commitment

Why Dual Certification?

Our Certification Process

Certificate Verification Support

Part 7: Quick Reference Guide

Certificate Verification Checklist

Laboratory Comparison Table

Red Flags Summary

Conclusion: Protecting Your Investment

Appendix: Verification Links & Contact Information

NGTC (National Gemstone Testing Center)

GIL (Gem International Laboratories)

Industry Resources

FOREVER STARJEWELRY FACTORY

GB/T 16552-2017《珠宝玉石名称》(Jewelry and Gemstones — Nomenclature)

GB/T 16553-2017《珠宝玉石鉴定》(Jewelry and Gemstones — Identification)

FOREVER STAR
JEWELRY FACTORY