body {
font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
line-height: 1.6;
color: #333;
max-width: 800px;
margin: 0 auto;
padding: 20px;
}
h1, h2, h3 {
color: #2c3e50;
}
.calculator-container {
background-color: #f9fbfd;
border: 1px solid #e1e4e8;
border-radius: 8px;
padding: 25px;
margin-bottom: 40px;
box-shadow: 0 4px 6px rgba(0,0,0,0.05);
}
.calculator-title {
text-align: center;
color: #d4af37; /* Gold color */
margin-bottom: 20px;
font-size: 1.5rem;
font-weight: bold;
}
.form-group {
margin-bottom: 15px;
}
.form-group label {
display: block;
margin-bottom: 5px;
font-weight: 600;
color: #555;
}
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width: 100%;
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border-radius: 4px;
font-size: 16px;
box-sizing: border-box;
}
.form-group .help-text {
font-size: 12px;
color: #777;
margin-top: 4px;
}
.calc-btn {
display: block;
width: 100%;
background-color: #d4af37;
color: white;
padding: 12px;
border: none;
border-radius: 4px;
font-size: 18px;
font-weight: bold;
cursor: pointer;
transition: background-color 0.3s;
margin-top: 20px;
}
.calc-btn:hover {
background-color: #b5952f;
}
#result-area {
margin-top: 25px;
padding: 20px;
background-color: #fff;
border: 1px solid #ddd;
border-radius: 4px;
display: none;
}
.result-row {
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justify-content: space-between;
margin-bottom: 10px;
padding-bottom: 10px;
border-bottom: 1px dashed #eee;
}
.result-row.final {
border-bottom: none;
font-weight: bold;
font-size: 1.2rem;
color: #2c3e50;
margin-top: 10px;
padding-top: 10px;
border-top: 2px solid #d4af37;
}
.result-value {
font-weight: bold;
}
.article-content {
background: #fff;
padding: 20px;
}
table {
width: 100%;
border-collapse: collapse;
margin: 20px 0;
}
table, th, td {
border: 1px solid #ddd;
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th, td {
padding: 12px;
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th {
background-color: #f2f2f2;
}
How to Calculate Old Gold Rate Before You Sell
Selling or exchanging old gold jewelry is a common financial practice, whether you are upgrading your collection or liquidating assets. However, many consumers are unaware of how jewelers calculate the value of used gold. Without understanding the math behind the Old Gold Rate, you risk receiving less than your jewelry is worth.
This guide explains the step-by-step process of valuing old gold, factoring in purity, net weight, and standard market deductions.
The Core Formula
The value of your old gold is determined by the pure gold content within the jewelry, multiplied by the current market rate. The formula is:
Value = (Net Weight × Purity Percentage × Current 24K Rate) – Deductions
1. Net Weight Calculation
When you weigh a piece of jewelry, you are measuring the Gross Weight. This includes gold, but also gemstones, enamel, beads, dirt, and even the springs inside clasps. Since jewelers only pay for the gold, they must subtract these non-gold elements.
- Gross Weight: Total weight on the scale.
- Stone/Impurity Weight: Estimated or measured weight of non-gold items.
- Net Weight: Gross Weight – Stone Weight.
2. Understanding Purity (Karats)
Gold purity is measured in Karats (K). 24K is pure gold, but it is too soft for most jewelry. Alloys (copper, silver, zinc) are added to strengthen it, reducing the purity.
| Karat |
Purity % |
Common Usage |
| 24K |
99.9% |
Coins, Bars |
| 22K |
91.6% |
Standard Jewelry (Hallmarked 916) |
| 18K |
75.0% |
Diamond Jewelry, Stone Settings |
| 14K |
58.3% |
Affordable Jewelry, US Standard |
3. Market Rate & Deductions
Jewelers base their buying price on the current 24K gold market rate. However, when buying old gold, they apply deductions:
- Melting Loss: When old jewelry is melted to verify purity, a small amount of gold is lost. Jewelers often deduct 1% to 3% for this.
- Exchange Depreciation: If you are taking cash instead of exchanging for new jewelry, the deduction might be higher (often 3% to 5%).
Example Calculation
Let's say you want to sell a 22K gold chain.
- Total Weight: 20 grams
- Current Market Rate (24K): 6,000 per gram
- Stones/Impurities: 0 grams (Plain gold)
- Deduction: 3%
Step 1: Determine Purity Value
Since it is 22K, the gold is 91.6% pure (22 ÷ 24 = 0.9166).
Step 2: Calculate Gross Value
20g × 0.9166 × 6,000 = 109,992
Step 3: Apply Deduction
Deduction = 3% of 109,992 = 3,299.76
Final Pay = 109,992 – 3,299.76 = 106,692.24
Why Does the Jeweler's Rate Differ?
Sometimes the rate displayed on the showroom board is for selling new jewelry (which includes overheads). The "buy-back" rate for old gold is strictly based on the bullion market price. Always ask the jeweler for their specific buy-back policy before transacting.
function calculateOldGold() {
// 1. Get Input Values
var marketRate = parseFloat(document.getElementById('marketRate').value);
var totalWeight = parseFloat(document.getElementById('totalWeight').value);
var stoneWeight = parseFloat(document.getElementById('stoneWeight').value);
var karat = parseFloat(document.getElementById('karatPurity').value);
var deductionPercent = parseFloat(document.getElementById('deductionPercent').value);
// 2. Validate Inputs
if (isNaN(marketRate) || marketRate <= 0) {
alert("Please enter a valid Market Price.");
return;
}
if (isNaN(totalWeight) || totalWeight <= 0) {
alert("Please enter a valid Total Weight.");
return;
}
if (isNaN(stoneWeight) || stoneWeight < 0) {
stoneWeight = 0; // Default to 0 if invalid but keep running if empty
}
if (isNaN(deductionPercent) || deductionPercent < 0) {
deductionPercent = 0;
}
// 3. Logic: Net Weight
var netWeight = totalWeight – stoneWeight;
if (netWeight <= 0) {
alert("Stone weight cannot be greater than or equal to total weight.");
return;
}
// 4. Logic: Purity Factor
// 24K = 1, 22K = 22/24, etc.
var purityFactor = karat / 24.0;
// 5. Logic: Value Calculation
// Value of the pure gold content in the item
var grossValue = netWeight * purityFactor * marketRate;
// 6. Logic: Deduction
var deductionAmount = grossValue * (deductionPercent / 100.0);
var finalValue = grossValue – deductionAmount;
// 7. Format Output
// Helper to format numbers with commas/decimals
function formatMoney(num) {
return num.toLocaleString(undefined, {minimumFractionDigits: 2, maximumFractionDigits: 2});
}
// 8. Display Results
document.getElementById('displayNetWeight').innerText = netWeight.toFixed(2) + " g";
document.getElementById('displayPurity').innerText = (purityFactor * 100).toFixed(1) + "% (" + karat + "K)";
document.getElementById('displayGross').innerText = formatMoney(grossValue);
document.getElementById('displayDeduction').innerText = "-" + formatMoney(deductionAmount);
document.getElementById('displayFinal').innerText = formatMoney(finalValue);
// Show result area
document.getElementById('result-area').style.display = "block";
}