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Pure Au and pure Ag, when fully annealed, show no proportionality of stress to strain in any part of the stress-strain diagram. The Young’s modulus E for silver was about 71 GPa (10.3 Mpsi) for an annealed (as received) specimen (room temperature assumed). The limit of proportionality was 17.9 MPa (1.3 ton/in2), and the 0.01 % proof stress was 45.5 MPa (3.3 ton/in2). Annealing a specimen for 1 h at 700 °C after 5 % overstrain in tension gave E =78 GPa (11.3 Mpsi). Tables of data for proportional limit, proof stress, maximum stress, and Young’s modulus for silver are given.