Gemstone & Precious Metal Weight Converter (Carats, Points, Grams, Troy Grains & Troy Ounces)

Convert metric carats into points, grams, troy grains, troy ounces, and round diamond mm.

Weight in Grams (1 ct = 0.200 g)
0.3 g
Jeweler Points (100 pts = 1 ct) 150 points
Weight in Troy Grains 4.63 grains
Approx. Round Brilliant Diameter 7.383 mm
Inputs
⚡ Scenarios:
ct
Gemstone weight in metric carats (1.00 ct = 0.200 g = 100 points).
Results & Graph
Weight in Grams (1 ct = 0.200 g)
0.3 g
Jeweler Points (100 pts = 1 ct)
150 points
Weight in Troy Grains
4.63 grains
Approx. Round Brilliant Diameter
7.383 mm

Weight in Grams (1 ct = 0.200 g)

Graph 1 • Carats ↔ Grams & Troy Ounces • Domain Architecture & Live Telemetry Maps Gemstone Weight Carats through Carats ↔ Grams & Troy Ounces Formula.
EVERYDAY & CULINARY CONVER Weight in Grams (1 ct = 0. 0.3 g Jeweler Points (100 pts = 150 points Carats ↔ Grams & Troy Ounces • Component Waterfall Weight in Grams (1 ct = 0.200 0.3 g Jeweler Points (100 pts = 1 ct 150 points Weight in Troy Grains 4.63 grains Approx. Round Brilliant Diamet 7.383 mm
Graph 2 • Weight in Grams (1 ct = 0.200 g) Across Gemstone Weight Carats Sweep (40% → 160%) Evaluates Grams = Carats × 0.200; Points = Carats × 100; TroyGrains = Carats × across 7 operating points (current input highlighted).
0 g 0.550 g 1.10 g 0.120 0.600ct 0.180 0.900ct 0.240 1.20ct 0.300 1.50ct 0.360 1.80ct 0.420 2.10ct 0.480 2.40ct
Graph 3 • Carats ↔ Grams & Troy Ounces Multi-Scenario Envelope Shows how Weight in Grams (1 ct = 0.200 g) responds across ±30% scenario shifts.
0 g 0.550 g 1.10 g 0.210 -30% 0.255 -15% 0.300 +0% 0.345 +15% 0.390 +30%
Summary: 1.5 carats (150 points) equals 0.3 grams (300 mg), 4.63 troy grains, and ~7.38 mm diameter in a standard Round Brilliant diamond cut.
Summary: 1.5 carats (150 points) equals 0.3 grams (300 mg), 4.63 troy grains, and ~7.38 mm diameter in a standard Round Brilliant diamond cut.
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Interactive chart & math engine powered by CalculatorGraph

Formula & Mathematical Methodology: Carats ↔ Grams & Troy Ounces Formula

Grams = Carats × 0.200
Points = Carats × 100
TroyGrains = Carats × 3.08647
RoundDiamondmm ≈ 6.45 × Carats1/3
Grams = Carats × 0.200; Points = Carats × 100; TroyGrains = Carats × 3.08647; RoundDiamond_mm ≈ 6.45 × Carats^(1/3)
  • gemstoneWeightCarats: Gemstone weight in metric carats (1.00 ct = 0.200 g = 100 points).

Rounding: Internal floating-point calculations run in 64-bit IEEE-754 double precision; display values round to 2–4 decimal places.

Worked Example: Carats ↔ Grams & Troy Ounces Worked Example

Convert metric carats into points, grams, troy grains, troy ounces, and round diamond mm.

  1. Enter the input measurement, system configuration, or astronomical parameter.
  2. Apply the standard conversion or analytical equation: Grams = Carats × 0.200; Points = Carats × 100; TroyGrains = Carats × 3.08647; RoundDiamond_mm ≈ 6.45 × Carats^(1/3).
  3. Inspect the primary metric, secondary equivalents, and 3 real-time SVG graphs.
Result: Computes Carats ↔ Grams & Troy Ounces via Grams = Carats × 0.200; Points = Carats × 100; TroyGrains = Carats × 3.08647; RoundDiamond_mm ≈ 6.45 × Carats^(1/3).

Frequently Asked Questions

How does the Gemstone & Precious Metal Weight Converter (Carats, Points, Grams, Troy Grains & Troy Ounces) perform the calculation?

It evaluates Grams = Carats × 0.200; Points = Carats × 100; TroyGrains = Carats × 3.08647; RoundDiamond_mm ≈ 6.45 × Carats^(1/3) directly in your browser and renders three custom SVG charts in real time.

Can I solve backwards for an input parameter using Goal Seek?

Yes. Click "🎯 Goal Seek" in the results toolbar to solve backwards for any numeric input field.

Does this tool work offline?

Yes. All calculations run 100% locally in your browser with full offline PWA support.

Unit Conversions · Everyday & Culinary Conversions

Gemstone & Precious Metal Weight Converter (Carats, Points, Grams, Troy Grains & Troy Ounces): inputs, method, and how to read the result

Convert metric carats into points, grams, troy grains, troy ounces, and round diamond mm.

Choose inputs for the case you are checking

The defaults are illustrative. Replace them with values for your case and keep the units shown beside each field.

  • Gemstone Weight Carats: Gemstone weight in metric carats (1.00 ct = 0.200 g = 100 points).

What the calculation includes

With the default values shown, Weight in Grams (1 ct = 0.200 g) is 0.3 g. The calculation follows Carats ↔ Grams & Troy Ounces Formula; the formula and variable definitions above show how the inputs combine.

One-input check: With the other defaults held constant, changing Gemstone Weight Carats from 1.5 ct to 1.65 ct changes Weight in Grams (1 ct = 0.200 g) from 0.3 g to 0.33 g. This is a comparison inside the calculator's stated model, not a prediction.

Where to use caution

  • Uses official NIST Special Publication 811, IEEE/RFC systems engineering, APA psychometric, and USNO astronomical formulas.
  • Empirical metallurgy and calendar conversions represent standard reference-condition approximations.

Scope: Global NIST, IEEE, APA & Astronomical Standard Check the assumptions and limitations against your situation before relying on the estimate.

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