But... "basalt fibers"??????? Basalt? Basalt? An igneous rock with high SG and prized as ballast in sailing vessels? I think not. Perhaps the BS Department got mixed between Boron, Basalt and bollocks.

Basalt fiber

Basalt fiber or fibre is a material made from extremely fine fibers of basalt, which is composed of the minerals plagioclase, pyroxene, and olivine. It is similar to carbon fiber and fiberglass, having better physicomechanical properties than fiberglass, but being significantly cheaper than carbon fiber. It is used as a fireproof textile in the aerospace and automotive industries and can also be used as a composite to produce products such as camera tripods.

Manufacture

The manufacture of basalt fiber requires the melting of the quarried basalt rock to about 1,400 °C (2,550 °F). The molten rock is then extruded through small nozzles to produce continuous filaments of basalt fiber. There are three main manufacturing techniques, which are centrifugal-blowing, centrifugal-multiroll and die-blowing. The fibers typically have a filament diameter of between 9 and 13 µm which is far enough above the respiratory limit of 5 µm to make basalt fiber a suitable replacement for asbestos. They also have a high elastic modulus, resulting in excellent specific tenacity - three times that of steel.[verification needed]

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Basalt is a natural volcanic rock that can be used in manufacturing and made into ultrafine gold fibers that are resistant to vibrations. Basalt fibers are woven longitudinally with Wilson’s [K]arophite Black to create a composite Wilson says is the most advanced in the industry.

Like noise-cancelling headphones that filter out unwanted external noise, says Wilson, basalt added to the matrix filters the unwanted extreme frequencies in the racquet. According to the company, the new BLX technology delivers cleaner feedback and better sensation — “a smoother signal reaches the hand.”