Quarks on land and sea and in the air

A search for quarks in meterorites, air, and sea water has been conducted by W. A. Chupka, J. P. Schiffer, and C. M. Stevens of Argonne National Laboratory [Phys. Rev. Letters 17, 60 (1966)]. Previous quark hunts have been conducted by looking for fractionally charged particles in the products of high‐energy collisions of particles from accelerators and cosmic rays. (In sum, these experiments set a probable lower bound of $5 BeV/c2$ on the quark mass.) The present work proceeds on the assumption that quarks are stable particles and looked for the chemical (or, more precisely, ionic) effects thai quarks would produce if they entered into combination with ordinary chemical species or other particles.