what are the materials required to make this?
Pure carbon, the belt press, the cubic press and the split-sphere (BARS) press.
High pressure, high temperature
In the HPHT method, there are three main press designs used to supply the pressure and temperature necessary to produce synthetic diamond: the belt press, the cubic press and the split-sphere (BARS) press. Diamond seeds are placed at the bottom of the press.
The internal part of press is heated above 1400 °C and melts the solvent metal. The molten metal dissolves the high purity carbon source, which is then transported to the small diamond seeds and precipitates, forming a large synthetic diamond.
when was the first man made diamond made 1954
Pure carbon crystallized in an isotropic 3D form Pure carbon, crystallized in an isotropic 3D form. Pure carbon
Synthetic diamond Synthetic diamond Synthetic diamond
Introduction Introduction Introduction
Synthetic diamond (also referred to as laboratory-grown diamond, laboratory-created diamond, or cultured diamond) is a diamond made of the same material as natural diamonds: pure carbon, crystallized in an isotropic 3D form. Synthetic diamond are different from both natural diamond, which is created by geological processes, and imitation diamond, which is made of non-diamond material.  ynthetic diamond (also referred to as laboratory-grown diamond, laboratory-created diamond, or cultured diamond) is a diamond made of the same material as natural diamonds: pure carbon, crystallized in an isotropic 3D form.  Synthetic diamond (also referred to as laboratory-grown diamond, laboratory-created diamond, or cultured diamond) is a diamond made of the same material as natural diamonds: pure carbon
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Synthetic diamond [SEP] High pressure, high temperature
However, such a press would be complex and difficult to manufacture. The BARS apparatus is claimed to be the most compact, efficient, and economical of all the diamond-producing presses. In the center of a BARS device, there is a ceramic cylindrical "synthesis capsule" of about 2 cm in size. The cell is placed into a cube of pressure-transmitting material, such as pyrophyllite ceramics, which is pressed by inner anvils made from cemented carbide (e.g., tungsten carbide or VK10 hard alloy). The outer octahedral cavity is pressed by 8 steel outer anvils. After mounting, the whole assembly is locked in a disc-type barrel with a diameter about 1 meter.