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Carat to mm, ring size converter, gold purity, gem value estimator, and jewelry calculators.
Convert gemstone carat weight to approximate diameter in millimeters.
Convert gemstone diameter in millimeters to approximate carat weight.
Convert ring sizes between US, EU, UK, and Japanese scales.
Estimate ring weight from dimensions, metal type, and band width.
Convert between karat, fineness, and percentage for gold purity.
Calculate silver purity and alloy composition from fineness or millesimal.
Calculate platinum purity and alloy percentages from hallmark stamps.
Calculate gold value from weight, purity, and current spot price.
Calculate silver value from weight, purity, and current spot price.
Estimate gemstone value from type, carat weight, cut, and clarity.
Evaluate diamond quality from cut, color, clarity, and carat weight.
Reference guide for pearl sizes, grades, and value by diameter.
Find ideal necklace chain length from neck size and style preference.
Calculate bracelet size from wrist circumference and desired fit.
Find ideal pendant size proportional to chain length and body frame.
Estimate earring weight from dimensions and metal type for comfort.
Look up density values for gold, silver, platinum, and common alloys.
Calculate alloy composition from base metal and additive weights.
Reference guide for precious metal hallmark stamps and their meanings.
Estimate jewelry insurance premium from appraised value and coverage type.
Reference for diamond grading using the 4Cs: cut, color, clarity, and carat weight.
Reference for ruby quality assessment: color saturation, clarity, and origin.
Reference for sapphire quality assessment: hue, tone, saturation, and treatments.
Reference for emerald quality assessment: color, jardins, and origin importance.
Reference guide for amethyst varieties, color grades, and identification tips.
Reference guide for topaz varieties: Imperial, Blue, White, and treatment types.
Reference guide for opal types: Black, White, Boulder, Fire, and play-of-color grading.
Reference guide for turquoise quality, matrix patterns, and mine identification.
Reference guide for garnet species: Almandine, Pyrope, Spessartine, and Tsavorite.
Reference guide for pearl types: Akoya, South Sea, Tahitian, and freshwater grading.
Reference guide for jade types: Jadeite vs Nephrite, grading, and identification.
Reference guide for lapis lazuli quality, pyrite inclusions, and origin grading.
Reference guide for tourmaline varieties: Paraiba, Rubellite, Indicolite, and Watermelon.
Reference guide for tanzanite grading, trichroism, and heat treatment effects.
Reference guide for alexandrite color-change evaluation, origin, and rarity.
Reference guide for spinel colors, notable specimens, and comparison with ruby.
Reference guide for natural zircon varieties, dispersion, and heat treatment.
Reference guide for peridot color grading, sources, and identification tips.
Reference guide for aquamarine color grading, clarity, and heat treatment.
Reference guide for moonstone adularescence, body color, and quality factors.
Complete Mohs mineral hardness scale with scratch test reference and examples.
Reference for the seven crystal systems: cubic, tetragonal, hexagonal, and more.
Step-by-step mineral identification using luster, streak, hardness, and cleavage.
Reference for igneous, sedimentary, and metamorphic rock classification.
Reference for geological eons, eras, periods, and epochs with major events.
Reference for gemstone setting types: prong, bezel, channel, pave, and tension settings.
Reference for prong types: 4-prong, 6-prong, V-prong, and shared prong settings.
Reference for bezel setting types: full, partial, scalloped, and rubover bezels.
Reference for channel settings: standard, bar, and flush channel construction.
Reference for pave settings: micro-pave, French pave, and bead-set pave techniques.
Reference for tension settings: spring tension, compression, and metal requirements.
Reference for flush (gypsy) settings: burnishing, hammer-set, and surface finishing.
Reference for jewelry clasp types: lobster, spring ring, toggle, magnetic, and box clasps.
Reference for chain types: cable, curb, rope, box, figaro, and snake chains.
Reference for jewelry wire: gauge sizes, hardness levels, and metal options.
Reference for bead types: seed, crystal, glass, gemstone, and spacer beads.
Reference for gemstone cuts: brilliant, step, mixed, cabochon, and rose cut.
Reference for gemstone shapes: round, oval, pear, marquise, emerald, and cushion.
Reference for metal finishes: polished, matte, brushed, hammered, and sandblasted.
Reference for jewelry plating: gold, rhodium, ruthenium, and PVD coating.
Reference for jewelry soldering temperatures by solder type and metal.
Reference for jewelry casting: lost-wax, centrifugal, vacuum, and sand casting.
Reference for wax carving tools, wax types, and techniques for jewelry models.
Reference for engraving types: hand, machine, laser, and rotary engraving techniques.
Reference for filigree techniques: wire curling, soldering, and design patterns.
Reference for granulation technique: bead making, placement, and fusion methods.
Reference for enameling types: cloisonne, champleve, plique-a-jour, and painted enamel.
Reference for resin jewelry: epoxy types, curing times, molds, and inclusion tips.
Reference for polymer clay: brand comparison, baking temps, and techniques.
Reference for metal clay: silver, gold, copper types, firing schedules, and shrinkage.
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