What Is 鑽石4C?
When buying a diamond, the term 鑽石4C refers to the four key factors that determine a diamond's quality and value: Cut, Color, Clarity, and Carat Weight. Developed by the Gemological Institute of America (GIA), the 4Cs provide a universal standard to evaluate diamonds.
Understanding the 4Cs helps buyers make informed decisions and find the right balance between quality and budget.
The 4Cs Explained
1. Cut（切工）
Cut refers to how well a diamond is shaped and faceted. It affects how light reflects within the diamond, impacting its brilliance and sparkle.
Excellent/Ideal Cut: Maximizes light reflection and brilliance.
Very Good Cut: Reflects most light well.
Good/Fair Cut: Reflects light less efficiently.
Poor Cut: Dull appearance due to light leakage.
✅ Tip: Among the 4Cs, cut has the most influence on a diamond’s appearance.
2. Color（顏色）
Color in diamonds is graded on a scale from D (colorless) to Z (light yellow or brown). The less color, the higher the grade and value.
D–F: Colorless – very rare and expensive.
G–J: Near colorless – great value with minimal visible tint.
K–M and beyond: Noticeable warmth or yellow tint.
✅ Tip: Choose G–H for a good balance of appearance and value.
3. Clarity（淨度）
Clarity measures the presence of internal flaws (inclusions) and surface blemishes. The fewer imperfections, the higher the clarity grade.
FL (Flawless) / IF (Internally Flawless)
VVS1 / VVS2 – Very, very slight inclusions
VS1 / VS2 – Very slight inclusions
SI1 / SI2 – Slight inclusions, sometimes visible to the naked eye
I1–I3 – Obvious inclusions, often visible without magnification
✅ Tip: VS1 or VS2 offers excellent clarity without high costs.
4. Carat（克拉重量）
Carat refers to the weight of the diamond. Larger diamonds have higher carat weights, but price rises exponentially with size.
1 carat = 0.2 grams
Price increases with carat size and rarity
✅ Tip: Choose slightly below popular sizes (e.g., 0.90ct instead of 1.00ct) for better value.
How to Use the 鑽石4C When Buying a Diamond
Set Priorities: Focus on what matters most—brilliance (cut), size (carat), or purity (clarity).
Balance Quality and Budget: You don’t need top grades in all 4Cs to get a beautiful diamond.
Request Certification: Ensure the diamond is certified by GIA or another reputable lab.
Compare Options: View different combinations of 4C grades to see what looks best to your eye and fits your budget.
Conclusion
Understanding the 鑽石4C is the key to choosing the perfect diamond with confidence. By learning how cut, color, clarity, and carat affect value and beauty, you can make an informed decision whether you're shopping for an engagement ring, a gift, or an investment.