induration

The voice was harder than I had known, and not only in stony reaction to long floods of wholly just selfpity, also roughened with gin and smoke, perhaps also assimilated to New York induration, the hardness of culture as well as of pain.

Both erythema and induration appear to be adequate indices of tuberculin sensitivity.

"Induration is a measure of rock "strength" and is defined as the ratio of the measured frame modulus to the maximum frame modulus allowed by the Gassmann-Biot model." Spratt, R. S.; Goins, N. R. and Fitch, T. J. (1993) "Pseudo-shear — The analysis of AVO." Castagna, John P. and Backus, Milo M. (eds.) Offset-Dependent Reflectivity — Theory and Practice of AVO Analysis. Series: Investigation in Geophysics volume 8. Tulsa : Society of Exploration Geophysicistspp. 37-56, page 37, isbn 978-1-56080-059-0.

"Induration of carbonate rocks proceeds predominately in the early stages (prior to diagenesis) by compaction and expulsion of fluids." Whittaker, Alun (1985) Formation Evaluation: Geological Procedures Dordrecht : Springer Verlag page 104, isbn 978-94-010-8861-9.