Which alloy has a temperature coefficient of resistivity close to zero, making it suitable for a temperature-independent resistance standard?

1. A resistance standard is useless if its value drifts as the laboratory warms up. 2. What is needed is a material whose temperature coefficient of resistivity is as near zero as possible. 3. Manganin, an alloy of copper, manganese and nickel, has a coefficient of 0.000 x 10^-3 per degree C. 4. Its resistivity therefore varies only slightly with temperature, which is exactly the property wanted. 5. Constantan is the close rival at 0.002 x 10^-3 per degree C, but it is not the smaller of the two. 6. Nichrome at 0.4 x 10^-3 and tungsten at 4.5 x 10^-3 per degree C both drift far too much. _Source: OpenStax College Physics (CC BY 4.0), Ch 20 "Electric Current, Resistance, and Ohm's Law", section Temperature Variation of Resistance_