(10/15 micron) carbon fibre: carbon fibres exhibit very strong antipathy to water and thus take on a silvery appearance when they are immersed in water.
 

 
so what is a carbon fibre?
a single carbon fibre is 10/15 microns in diameter, amorphous black carbon (graphite) throughout and is described as having nil stretch :-

carbon fibre can be etched on its (otherwise smooth) surfaces and coated with a kind of glue sizing to make it useful in bulk when mixed with epoxy resin: very useful to engineers and scientists...

When they are clean, they can be used in micro-sugery as sutures (stitches).
Not only do carbon fibres exhibit very strong antipathy to water, they are so small that thousands of them wrapped in a tight bunch, for instance, to form the core of a wire-wound music string, will still occupy a bundle diameter of only the order of 1mm.

this should image-swap on mouse over!all about 7