Findings and award set aside.
Theodore G. McKesson, Thomas P. Riordan, James D. McKesson, all of Phoenix, for petitioner.
Robert Yount, of Phoenix, H. S. McCluskey and Donald J. Morgan, of Phoenix, of counsel, for respondent Industrial Commission.
Phelps, Justice. La Prade, C. J., and Udall, Stanford and De Concini, JJ., concurring.
[70 Ariz. 434] A motion for rehearing was granted in this case for the purpose of correcting an erroneous statement in the original opinion concerning the geological and chemical character of silicon dioxide and any erroneous conclusions of law or fact naturally or necessarily flowing therefrom. We adopt as a part of this opinion on rehearing the statement of facts and the quotations from the evidence in the original decision, the same as if they were incorporated herein.
In our original opinion we unfortunately relied solely upon the record made by both counsel for the commission (acting as Referee) and counsel for the applicant as our source of information concerning the character of silicon dioxide and we especially relied upon the evidence elicited by the Referee to the effect that silicon dioxide results from the oxidation of silica, thus making a clear distinction between silica and silicon dioxide. Basing our opinion upon that evidence we said that silicon dioxide dust could only come into existence after an oxidation of silica.
[70 Ariz. 435] The fact is that silica and silicon dioxide (SiO) are identical, the one being the geological and the other the chemical name for the same thing. Quartz is crystallized silicon dioxide. Quartz is pure silica. Quartz dust and silicon dioxide dust are identically the same thing.
Silicon (Si) forms 28.06% of the earth's crust and exists only in combination either as an oxide or with elements to form silicates. In these two forms it is the predominating constituent of all but calcareous rock. As silica (SiO) or quartz it forms one of the most indestructible natural compounds and hence is to be found as a prevailing constituent in nearly all sands and soil. See "Rocks, Rock Weathering and Soils" pages 4 and 5 by George P. Merrill, a recognized authority on this subject; also Webster's New International Dictionary, Second Edition.
The above scientific knowledge, admittedly newly acquired by attorneys for petitioner, is confirmed by briefs amici curiae. These briefs are sufficiently exhaustive in their treatment of the subject to form the basis of a liberal education concerning the character of silica, silicates, silicon and silicon dioxide, for which we are deeply grateful.
Counsel for the commission in its brief in response to applicant's motion for rehearing declines to accept any responsibility for the error committed by the court as to the character of silicon dioxide dust or to acknowledge ignorance of its character although the record shows that it was through the questioning of the ...