Gemstone mm to Carat Calculator

Carat Weight Formula:

\[ Carat = L \times W \times D \times SG / 2280 \]

Length (L):

Width (W):

Depth (D):

Specific Gravity (SG):

unitless

Estimated Carat Weight:

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1. What is the Gemstone mm to Carat Calculator?

The Gemstone mm to Carat Calculator estimates the weight of a gemstone in carats based on its dimensions (length, width, depth) and specific gravity. This formula provides an approximate weight calculation commonly used in gemology and jewelry.

2. How Does the Calculator Work?

The calculator uses the standard gemstone weight formula:

\[ Carat = L \times W \times D \times SG / 2280 \]

Where:

\( L \) — Length of the gemstone (mm)
\( W \) — Width of the gemstone (mm)
\( D \) — Depth of the gemstone (mm)
\( SG \) — Specific gravity of the gemstone material (unitless)
2280 — Conversion factor for mm³ to carats

Explanation: The formula calculates the volume in cubic millimeters and converts it to carats using the specific gravity and conversion factor.

3. Importance of Carat Weight Estimation

Details: Accurate carat weight estimation is crucial for gemstone valuation, jewelry design, and purchasing decisions. It helps determine the approximate value and size of gemstones before cutting or setting.

4. Using the Calculator

Tips: Enter all dimensions in millimeters and the specific gravity of the gemstone material. Common specific gravities: Diamond (3.52), Ruby/Sapphire (4.00), Emerald (2.72), Quartz (2.65). All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: How accurate is this calculation?
A: This provides an approximate weight. Actual weight may vary based on cut precision, inclusions, and shape variations.

Q2: What is specific gravity and why is it important?
A: Specific gravity is the ratio of a material's density to water's density. Different gemstones have different densities, affecting their weight for the same dimensions.

Q3: Can I use this for irregular shaped gemstones?
A: This formula works best for regularly shaped gemstones (oval, round, square). For irregular shapes, use average dimensions or specialized methods.

Q4: Why is the conversion factor 2280?
A: 2280 is derived from the density conversion and standard carat definition (1 carat = 0.2 grams), adjusted for millimeter measurements.

Q5: What are common specific gravity values for popular gemstones?
A: Diamond: 3.52, Ruby/Sapphire: 4.00, Emerald: 2.72, Aquamarine: 2.68, Topaz: 3.53, Garnet: 3.60-4.20, Pearl: 2.60-2.85.