Complete collection of jewelry knowledge
Carat (Ct) is the unit of mass (weight) of gemstones. Now 1 carat is equal to 0.2g or 200mg .. One carat is divided into 100 minute, such as 50 minutes or 0.5 carat, which is used to calculate smaller gemstones.
Clarity: Clarity includes two parts, namely, the original defects in the gem and the defects on the diamond surface caused by processing.
Defects: generally refers to the dirt, cracks, spots, lines, inclusions and other defects on the surface and inside of jewelry and jade. Pits or rust spots on the surface can be removed by reprocessing or polishing as long as they do not penetrate into the interior; Internal cracks, lines and gas, liquid and solid inclusions can only be reduced or eliminated by various improvement measures.
Fire color, also known as fire. The colored light reflected from the inside of a faceted gem. Its meaning is as follows: ① When white light enters the faceted gemstone and is reflected or transmitted out of the gemstone, the light is decomposed by the refraction of various wavelengths constituting the white light at different angles, and the spectral color is the spectral color displayed on the surface of the faceted gemstone through dispersion effect. Colorless and transparent faceted gems can show the dispersion effect of white light well; The body color and transparency of colored faceted gemstones will affect the color, purity and brightness. The cutting type, cutting ratio and polishing quality of gemstones have influence on the quality of fire color. ② Some literatures emphasize that fire color is a comprehensive expression of dispersion effect and flash effect. It is considered that gems with low dispersion value can also show good fire color as long as they are polished well.
Exposed bottom: if the proportion below the waist of the gem is too shallow, the optical fiber will flow away from the bottom or side and lose its luster, and the value of the gem will become lower.
Too thick ass: if the proportion of gems below the waist is too deep, a black background will appear, and the light will flow away from the side and lose its luster.
Cloud: Hazy, milky white and unclear natural inclusions, often consisting of a large number of tiny inclusions. The monomer of the inclusion can't be distinguished by 10 magnification, and the cloud inclusion often affects the transparency and brightness of the diamond, forming a hazy appearance.
Strike mark: the mark left by the impact of external force on a gem.
Faceted gemstone: A gemstone with a smooth geometrically polished surface.
Egg surface, plain surface: refers to non-faceted gems, without regular polished surfaces with geometric shapes such as round gems.
Burning or not burning: refers to heat treatment and optimization, without overheating treatment. GRS, Guberlin, GIA and other international certificates, you don't need to burn them when you meet.
Dispersion, the light entering the gem is internally reflected according to different tangent angles, and the distributed reflection of the light produces seven colors of the rainbow. This phenomenon is called dispersion.
Fire chroma: the intensity of seven-color general light reflected by gem decomposition is closely related to tangent ratio and symmetry.
Dove blood red: Dove blood red is a commercial concept. Because the fresh arterial blood of adult pigeons is close to this strange red color, so this ruby is named? Pigeon blood red? .
Royal blue: the color of royal blue is bright blue with purplish hue, which has a rich, deep, noble and elegant temperament. Royal sapphire is a high-quality sapphire tool in the market because it has considerable requirements on hue, concentration and saturation.
Cornflower Blue: The "cornflower" sapphire in Kashmir has always been regarded as the best of sapphires, showing a strong blue color with a slightly hazy purplish hue, giving people a velvet appearance.
Starlight: Also known as starlight effect, this is a reflection effect formed by two intersecting bands of primary colors passing through the surface of a gem. It is usually formed by the reflection of starlight in all directions by fine fibers or needle defects, which are divided into 6 beams, 4 beams or even more rare 12 beams. Ruby and sapphire are prone to this phenomenon.
Polychromaticity: Gems will show different colors from different angles.
Halo: This is the rainbow-like effect of many gems, which is caused by cracks or structural layers that block light into a special color. Black opal is a gem that can show this effect. And for pearls, the halo becomes? Pearl luster? .
Cat's eye: does the phrase Chatoyancy come from French? Chat (Cat) Then what? Oeil？ (eye), now commonly known as? Cat eyes (? Cat's eye ), meaning cat's eye. Because there are many gems in nature, when they are cut into curved surfaces, there will be a bright light band with certain swimming (flash or living light) on their curved surfaces, which is named after the slender pupil of the cat's eye. Nowadays, cat's eye refers to emerald cat's eye, while other gems with cat's eye effect need to be named as gems, such as apatite cat's eye and sillimanite cat's eye.
Discoloration: Discoloration gems refer to those gems whose colors change obviously when observed under two different light sources. Gems with this phenomenon are: golden emeralds, sapphires and color-changing garnets.
Mosaic: The common methods are: Mosaic, Nail Mosaic, Groove Mosaic and Cross Mosaic.
Pointed inlay: This is the most commonly used gemstone inlay method. These metal harrows are equipped with small metal claws, which have clamps like vises and bend to the waist of the gemstone, thus ensuring that the gemstone has a safe and lasting position. Rake inlay? .
Bead edge: the edge with beads and folds along the direction of steel strip, which makes the edge have the effect of coin edge.
Sandblasting: A matte, dull surface effect, usually used for precious metal jewelry.
Lobster clasp: A clasp shaped like a shrimp claw when jewelry is fixed or fastened. This buckle has a spring arm, which can firmly lock the shrimp claw.