Platinum Metals Review - Volume 4, Issue 2, 1960

A new technique, based upon electrochemical phenomena, has led to the development of the solion, the name given to a range of versatile detector and control devices that supplement both the thermionic valve and the transistor. Solions have special advantages at low potential owing to their extremely low power requirements and to the simplicity of the circuitry involved. This article outlines the principles underlying their design and development and the operating characteristics of a number of distinctly different types of solium. Generally, they comprise an electrolyte of iodine and potassium iodide, with platinum electrodes.

Concluding his article from the January issue of “Platinum Metals Review”, Dr Preston deals with the application of platinum and its alloys as a means of protecting refractories from attack by molten glass, with the production of fibre glass through platinum bushings, and with other applications of platinum in glass melting practice.

This article, a communication from the Johnson Matthey Research Laboratories, describes the development of a stable platinum plating bath capable of producing heavy and bright deposits on a wide range of base metals. This bath has been given the name DNS Platinum Plating Solution.

A sensitive thermocouple, of much greater response than the well-known platinum : rhodium-platinum combinations, and free from the oxidation problems associated with base metal thermocouples, is provided by a palladium-gold alloy and an iridium-platinum alloy. This article describes recent investigations that confirm the usefulness of this thermocouple at temperatures up to 1000°C.

In the Treasury of St. Peter’s in Rome there is a large and very fine chalice, consisting entirely of platinum. It is of great historical interest, having been made as long ago as 1788 from the first platinum produced in malleable form and in the following year presented to Pope Pius VI by Charles III, King of Spain.