Description

An early and important quartz’s cut parallel section signed by Werlein and bearing the manuscript inscription “Quartz parallèle Mr Curie”. According with the Werlein’s label [Médaille d’or Exp de 1878 et 1889 Ivan Werlein Paris”], this Curie-section was made in the early 1890s’ so before the discovery of radioactivity thanks to the Curie’s method.

In 1880, “The brothers [Jacques and Pierre] Curie thought there would be a direct correlation between the potential generated by temperature changes and the mechanical strain that gave rise to piezoelectricity. They expected that a piezoelectric effect would arise in materials with certain crystal asymmetries. Armed with the crudest of materials — tinfoil, glue, wire, magnets, and a simple jeweler’s saw — they tested various types of crystals, including quartz, topaz, cane sugar, Rochelle salt, and tourmaline. As a result, the Curies found that when such materials were compressed, the mechanical strain did indeed result in an electric potential. The strongest piezeoelectric effects were found in quartz and Rochelle salt. The brothers put their discovery immediately to good use by inventing the piezoelectric quartz electrometer.”

In 1898, with the quartz electrometer or balance, the Curie’s, Pierre and Marie, measured for the first time the charge of radioactivity.

Today, the piezo-quartzs preserve in the Institutions seems to be from later production manufactured by the Société Centrale des Produits Chimique, durint the early 20th century.

We know, from the contemporary publications, that Ivan Werlein, the best maker in crystal slides in Paris from the time, made the first quartz for the Curie’s brothers during the 80s’ and the 90s’, then the Société Centrale des Produits Chimique.

So this is a very early preserved example, extremely rare in private hands and on the market, of slide proving piezoelectricity and used in one of the first major physical discovery of the modern time : radioactivity.

The slide measures 50x17mm, it comes with a collection of other slide and crystals cuts.