Our Understanding of Diamonds Diamonds, the most precious of the five major gemstones, symbolize purity, loyalty, and eternal brilliance. They are the perfect representation of love, with diamond rings becoming the most important token of marriage. Diamonds also appreciate annually by 5%-10% or even more, making them a beloved luxury item. However, because diamonds are …
Gemstone (Gem) Mohs hardness (Hardness) Specific Gravity (Specific Gravity) Refractive Index (Refractive Index) Reflectivity (Reflectivity) Double Refraction (Double Refraction) Dispersion (Dispersion) Synthetic Rutil (Synthetic Rutil) 6.5 4.25 2.76 19.75 0.287 0.330 Synthetic Moissanite (Synthetic Moissanite) 9.25 3.22 2.67 20.67 Strained 0.104 Lithium Niobate (Lithium Niobate) 5.5 4.64 2.55 14.87 0.090 0.130 Diamond (Diamond) 10 3.52 …
Identification Characteristics of Diamonds and Their Simulants Read More »
Currently, the world’s popular high-temperature and high-pressure diamond synthesizing equipment mainly consists of two-sided tops (belt, which is mainly popular in Europe and the United States), six-sided tops (unique to Mainland China), and splitting spheres (barssplitsphere, Russia) or modified splitting spheres (Gemesis Company). In 1954, before Christmas, the General Electric Company in the United States …
Diamond Synthesis Method — High Temperature and High Pressure Read More »
In 1994, Thomas R. Anthony et al. of GE filed U.S. Patent 5,437,891 (issued in 1995) stating that the growth rate of cubic facets (100) of polycrystalline diamonds can be increased by chemical vapor deposition (CVD). In particular, if a small amount (e.g., 1%) of air (78% nitrogen, 21% oxygen, 1% argon) is added to …
chemical vapor deposition of diamond monocrystalline Read More »
Natural diamonds are produced at depths of over 130 kilometers. It has a unique cubic crystal structure. Each carbon atom in a diamond is bonded to four other carbon atoms, making it the hardest natural substance known in the world. How are diamonds formed? Let’s find out!
How to make diamonds by chemical vapor deposition? Chemical vapor deposition (CVD) produces pure, high-performance solid materials. A small diamond, which serves as the “core”, is placed in a vacuum environment to remove impurities and injected with high temperature gases – methane and hydrogen – at 3,000 degrees Celsius, which cracks to form electrically charged …
Diamond Synthesis Method – Chemical Vapor Deposition Read More »
Diamond Synthesis Method Diamonds can be synthesized by gas-phase methods (e.g., PVD or CVD), liquid-phase methods (e.g., hydrostatic, catalytic, or CVD liquid-phase methods), or solid-phase methods. The solid-phase method is the synthesis of diamonds in a material with no fluid. The solid carbon atoms cannot diffuse through the fluid to reorganize into the structure of …
Subtlety Comparison Table of Diamond Micro Powder Standards JB/T7990-1979 GB6966-86 JB/T7990-1998 QB/HH1801-04 Corresponding number 0-0.25 W0.5 0-0.05 M0/0.5 0-0.5 W1 0-1 M0/1 0-1 M0.5/1 0.5-1 0.5-1 M0.5/1.5 0.5-1.5 0.5-1.5 M0/2 0-2 W1.5 0-2 M1/2 1-2 0.5-3 12000 W2.5 1.5-3 M1.5/3 1-3 10000 1.5-3 8000 2-3 7000 W3.5 2-4 M2/4 2-4 6000 W5 2.5-5 M2.5/5 2-5 …
Subtlety Comparison Table of Diamond Micro Powder Standards Read More »
Subtlety Comparison Table of Synthetic Diamond with Foreign Standards China ISO FEPA America ANSI B74.16-1971 Japan JIS4130-1988 Germany DIN848-1988 Russia OCT9206-80 grit Size Microstructure Ⅰ Microstructure Ⅱ Size Grit Size grit Size Grit Size Microstructure Size Grit Size 40/45 425/355 426 —- 425/355 D426 425/355 40/50 425/300 40/50 425/300 D426 425/355 630/500 630/500 45/50 355/300 …
Subtlety Comparison Table of Synthetic Diamond with Foreign Standards Read More »
