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The electro‐oxidation of formaldehyde at copper is examined in relation to the process of electroless plating (EP) of copper. RBS and AES analyses show that Pd catalyst migration from the deposit‐substrate to the deposit‐solution interface during the EP process is negligible. This is the case for either Cu or Ni EP deposits, and when either wet or evaporated Pd catalyst is employed. The catalytic electro‐oxidation of H2CO thus proceeds during the EP process at a copper surface with no significant coverage by any other metal atoms. It is shown that the mechanism and measured rates of H2CO electro‐oxidation at copper can be understood on the basis of recent data for relevant copper/gas systems, and some special characteristics of the copper/alkaline solution system. Detailed calculations show that H2 , rather than H2O , is expected to be the final product of H2CO electro‐oxidation at copper at potentials as high as +0.4V vs. RHE, provided the activation energy for recombinative hydrogen desorption from the copper surface is less than 10 kcal/mole.

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The solubility behavior of C in olivine has been investigated using the 12C(d, p)13C nuclear reaction analysis technique. The technique provides an in situ microanalysis of concentration as a function of depth below the surface. In the case of olivine the depth profile extends to approximately 2.6 μn. Microbeam capability is achieved by focusing the deuteron beam with a superconducting solenoid. However, thermal degradation of the sample imposes a practical limit on the lateral spatial resolution of approximately 150 μm. The detection limit for C in forsteritic olivine is 65 ppm (atomic) and limited mainly by important background contributions from both Mg and Si. Olivines of similar compositions (Fo90–92) but from diverse geologic environments were studied, including (l) olivine crystallized in the presence of saline hydrothermal fluid in the shallow crust, (2) upper mantle megacrysts and crystals separated from spinel Iherzolite xenoliths from alkali basalts, (3) natural crystals equilibrated with graphite and magnesite at 30 kbar and 1400°C, and (4) olivine from a diamond‐bearing garnet Iherzolite xenolith from a kimberlite. Contrary to expectation based on previous experiments, none of the samples were found to contain C in concentrations greater than the detection limit. Concentration profiles generated by the use of combined sputtering and Auger techniques demonstrate that the adsorbed C‐rich layer on polished surfaces is typically restricted to the upper 100 Å of the surface.

Twenty‐four cast copper crotals (commonly called bells), one 'spilled bell’, one tinkler bell and a number of minerals from locations throughout the Greater Southwest were analysed for their elemental composition by a PIXE nuclear microprobe at Los Alamos National Laboratory, New Mexico, USA. Sixteen bells contained minor and trace amounts of silver, antimony, arsenic, lead, and in some cases tin, strontium, and selenium. Nine bells contained little or no detectable amounts of these elements. This suggests that several workshops throughout the Greater Southwest and Mexico might have manufactured these bells.