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Rate Calculation
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How to Calculate Gold & Silver Rate as per Purity: Formulas, GST & Making Charges
Master the mathematical formulas behind 24K, 22K, 18K and 14K rates, understand how making charges and 3% GST are computed, and watch our embedded video tutorial.
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TABLE OF CONTENTS
1. Understanding Purity Math & Karat Conversions2. The Universal Jewellery Invoice Formula3. Real Worked Example: Buying a 10g 22K Gold Bangle4. Silver Rates & Purity Math: 999 Bullion, 925 Sterling & 800 Pooja Silver5. Old Metal Exchange: How Purity Deductions Work (Hypothetical Illustration)▶ Video Tutorial Guide? Frequently Asked Questions
1. Understanding Purity Math & Karat Conversions
The purity of gold is measured in Karats out of a 24-part base. When you view our live market rate board, the published rates correspond precisely to these mathematical ratios:
• 24 Karat (99.9% / 99.5%): Benchmark fine bullion
• 22 Karat (91.6%): Standard hallmarked jewellery
• 18 Karat (75.0%): Diamond and stone-studded ornaments
• 14 Karat (58.3%): Lightweight and modern daily wear
Karat Purity Formulas
Rate of 22K/g = Rate of 24K (99.9) * (22 / 24) = 24K Rate * 0.9167
Rate of 18K/g = Rate of 24K (99.9) * (18 / 24) = 24K Rate * 0.7500
Rate of 14K/g = Rate of 24K (99.9) * (14 / 24) = 24K Rate * 0.5833
2. The Universal Jewellery Invoice Formula
When purchasing any gold jewellery article in India, your computerized invoice must strictly follow this transparent sequence:
Step A: Determine Net Weight = Gross Weight - Stone/Lac Weight
Step B: Calculate Gold Value = Net Weight * Applicable Karat Rate per gram
Step C: Add Making Charges (MC)
Step D: Apply 3% GST on (Gold Value + Making Charges)
Universal Master Gold Invoice Formula
Final Invoice Amount = [ (Net Gold Wt in g * Karat Rate per g) + Making Charges ] * 1.03
3. Real Worked Example: Buying a 10g 22K Gold Bangle
Let us calculate the exact cost of a 10.00 gram 22K BIS Hallmarked gold bangle assuming the 22K benchmark rate is ₹12,760 per gram with 10% making charges:
1. Net Gold Weight: 10.000 grams
2. Gold Base Value: 10.000 * ₹12,760 = ₹1,27,600.00
3. Making Charges (10%): ₹1,27,600 * 10% = ₹12,760.00
4. Subtotal before Tax: ₹1,27,600 + ₹12,760 = ₹1,40,360.00
5. GST (3% uniform): ₹1,40,360 * 3% = ₹4,210.80
6. Total Net Payable: ₹1,44,570.80
10g 22K Bangle Calculation Summary
10g × ₹12,760/g + 10% Making Charges + 3% GST:
4. Silver Rates & Purity Math: 999 Bullion, 925 Sterling & 800 Pooja Silver
Just like gold, silver pricing follows transparent purity benchmarks based on fine 99.9% (999) bullion:
A. The 3 Silver Purity Standards in India:
• 999 Fine Silver (99.9%): Pure bullion bars, chandi sikka (coins), and investment biscuits.
• 925 Sterling Silver (92.5%): Internationally recognized standard for fine silver jewellery, chains, designer rings, bracelets, and oxidised contemporary silverware (7.5% copper alloy adds strength).
• 800 - 850 Traditional Silver (80.0% – 85.0%): Widely crafted for traditional Indian pooja utensils, heavy kalash, niranjan, idols, payal (anklets), and bichiya (toe rings) where rigidity is essential.
B. Benchmark Conversion (Per Kg vs Per Gram):
Silver rates on commodity markets are quoted per 1 Kilogram (1,000 grams). To find the benchmark bullion rate per gram:
Rate per gram = Rate per kg / 1,000.
For example, if silver is ₹1,83,000 per kg, the 999 benchmark rate is ₹183.00 per gram.
C. How Purity-Adjusted Silver Rates are Derived:
• 925 Sterling Rate per gram = Benchmark 999 Rate * (92.5 / 99.9) ≈ 999 Rate * 0.9259
• 800 Pooja Silver Rate per gram = Benchmark 999 Rate * (80.0 / 99.9) ≈ 999 Rate * 0.8008
D. Silver Making Charges (घडणावळ):
Unlike gold where making charges are usually percentage-based, silver articles are typically priced with flat per-gram making charges (e.g., ₹12 to ₹30 per gram for plain casting, or ₹30 to ₹60 per gram for intricate hand-embossed antique / filigree work).
E. Worked Example: Buying a 50g 925 Sterling Silver Hallmarked Payal (Anklet)
Assuming 999 Bullion Rate = ₹183/g and 925 Making Charges = ₹25/g:
1. 925 Silver Base Rate: ₹183 * 0.9259 = ₹169.44 per gram
2. Silver Metal Value (50g): 50 * ₹169.44 = ₹8,472.00
3. Making Charges (₹25/g): 50 * ₹25 = ₹1,250.00
4. Pre-tax Subtotal: ₹8,472 + ₹1,250 = ₹9,722.00
5. GST (3% uniform): ₹9,722 * 3% = ₹291.66
6. Total Net Payable: ₹10,013.66
F. Worked Example: Buying a 200g 800-Purity Traditional Pooja Kalash
Assuming 999 Bullion Rate = ₹183/g and Pooja Utensil Making Charges = ₹15/g:
1. 800 Silver Base Rate: ₹183 * 0.8008 = ₹146.55 per gram
2. Metal Value (200g): 200 * ₹146.55 = ₹29,310.00
3. Making Charges (₹15/g): 200 * ₹15 = ₹3,000.00
4. Pre-tax Subtotal: ₹29,310 + ₹3,000 = ₹32,310.00
5. GST (3% uniform): ₹32,310 * 3% = ₹969.30
6. Total Net Payable: ₹33,279.30
Silver Purity & Master Billing Formulas
Rate 925 Sterling = Rate 999 Fine * (92.5 / 99.9)
Total Silver Bill = [ (Weight in g * Purity Rate/g) + (Weight * Making Charge/g) ] * 1.03
5. Old Metal Exchange: How Purity Deductions Work (Hypothetical Illustration)
When exchanging old jewellery, purity is tested in front of you using computerized XRF spectrometry. Because old ornaments contain solder joints (टाका) and may need refining, jewellers apply a transparent valuation formula.
Hypothetical Illustration (strictly for mathematical explanation):
Suppose you bring an old gold chain tested at 22 Karat (91.6% purity) weighing 10.00 grams. For illustrative purposes only, assuming a hypothetical 3% refining deduction:
• Gross & Net Gold Weight: 10.000 grams
• Pure 24K Gold Content: 10.000 * 91.6% = 9.160 grams
• Less Hypothetical 3% Refining Melting Deduction (illustrative only): 9.160 * 3% = 0.275 grams
• Net Realisable Pure Gold: 9.160 - 0.275 = 8.885 grams
• Value at benchmark 24K rate (say ₹13,920/g): 8.885 * ₹13,920 = ₹1,23,679.20 credited directly toward your new purchase!
Note: Actual exchange terms depend on test results and daily trade rates. The 3% figure is purely a hypothetical numerical example.
100% In-Front-Of-Customer Testing
At Mhaswadkar Saraf, melting, assaying, and XRF spectrometer testing are performed openly in our dedicated customer testing bay with zero hidden charges.
How to Calculate Gold Jewellery Price Step-by-Step
Comprehensive video walkthrough explaining gold rate conversions, net weight deductions, making charges, and GST calculations on tax invoices.
Frequently Asked Questions
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Mhaswadkar Saraf Private Limited
CIN: U74900PN2012PTC143175 • BIS Gold: HM/C-3879591 • BIS Silver: HM/C-7590180626
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