Gold Purity, Weight and Value: Understanding the Real Worth of Your Jewelry

When buying, selling, or appraising gold jewelry, three variables determine its real worth: purity (karats or fineness), weight (grams or traditional units), and the current market price of pure gold. This guide shows how to calculate the metal value of any gold item — and why retail prices often differ from bullion value.

1) Purity: Karats vs. Fineness

Karats describe how much pure gold is in an alloy:

• 24K — pure gold (99.9%)
• 22K — 91.6%
• 18K — 75%
• 14K — 58.5%

For the detailed karat breakdown, see: Understanding Gold Hallmarks .

2) Weight: Grams, Tola, Vori and More

Most modern jewelry is weighed in grams, but in South Asia and Southeast Asia, traditional units remain common:

• 1 tola / vori ≈ 11.6638 g
• 1 baht ≈ 15.244 g
• 1 chi = 3.75 g
• 1 troy ounce = 31.1035 g

For a full conversion chart, see: Gold Conversion Guide .

3) Market Price: Spot Rate of Pure Gold

The global gold market quotes prices per troy ounce of pure gold. To get a per-gram value:

spot_per_gram = spot_per_ounce / 31.1035

Need a full breakdown? See: How Gold Is Priced .

4) Core Formula: How to Calculate Metal Value

To find the bullion value of a jewelry piece:

pure_gold_weight_g = total_weight_g × (karat / 24)
metal_value = pure_gold_weight_g × (spot_per_gram)

This gives the value of pure gold content only — not the full retail price.

5) Why Retail Price Is Higher Than Metal Value

Jewelry costs more than its bullion value due to:

• Making charges (craftsmanship, labor, finishing)
• Design complexity (hand engraving, stone setting)
• Brand premium (heritage brands add significant markup)
• Wastage factors in manufacturing
• Taxes and duties

6) Practical Examples

A) 18K ring weighing 5 g

1. Purity = 18K → 18/24 = 0.75
2. Pure gold content = 5 × 0.75 = 3.75 g
3. Metal value = 3.75 × spot_per_gram

B) 22K bangle weighing 30 g

1. Purity = 22K → 22/24 = 0.9167
2. Pure gold content = 30 × 0.9167 ≈ 27.50 g
3. Metal value = 27.50 × spot_per_gram

7) How to Understand Appraisals

• Check the hallmark (e.g., 750, 916, 585)
• Confirm the weight on a calibrated scale
• Ask if the price reflects net weight or includes stones
• Know the current spot price

Summary

The real value of gold jewelry comes from the combination of purity, weight, and the current market price. Retail price includes craftsmanship, artistry, and brand value — making each piece more than just its metal content.