The size, diameter, or "count" of a yarn can be expressed in many ways. The modern international method used is the TEX system. The "TEX NUMBER" indicates the weight of yarn in grams per KM. of length.
Several ends of yarns can be twisted or braided to produce the yarn or rope of a higher diameter. The yarn can be reinforced with ductile metal wire such as brass, copper, zinc, lead, inconel, monel, stainless steel, etc. Reinforcement with filaments of metal wire offers particular properties in the end product such as heat dissipation, high temperature resistance, strength retention or particular friction properties. It can also be spun in combination with cotton or yarns made with man-made fibres to give an added advantage of higher strength and flexibility in lower temperature applications.
Asbestos yarn can also be treated with high quality lubricants, oil resisting compounds, PTFE and coated with flake graphite or mica for specific applications.