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Picture discs can be made by using different materials: cardboard, paper, shellac, plastic, glass, aluminum, vinyl, cellulose - that is to say, just about any medium that can be used to reproduce grooved sounds. The first 78rpm picture discs were made in Germany (and France) some 110 years ago. They were printed picture postcards covered with a transparent film into which the grooves were pressed. The story is detailed on my website http://www.lotz-verlag.de/Online-Disco-Phonocards.html Just try the various links for images of the patent issued to Thomas in 1904, and scans of specimen. Similar technologies were revived in Germany during the 1920s for 10" discs (I have test pressings). The first 33rpm picture discs were manufactured by RCA Victor in March 1933 The Nazi records mentioned (including those featuring Hitler's portrait or the swastica flag - I showed those at last year's Rochester ARSC meeting when discussing the German record label book) were 20cm and 25cm cardboad discs distributed by Nationaler Schallplattendienst from Berlin for election campaigns in 1932. Der Laut records mentioned also manufactured 30cm diameter picture disc, also cardboad. German manufacturers experimented with all sorts of carriers during that period. For instance, Metallophon used a metal core from 1931, covered with layers of cellulose ester. The first microgroove picture discs were made in Germany during the mid 1950s by BB-Schallplatten. The picture disc technology was refined over the vinyl era, when they were mostly made of five layers. "Two transparent sheets of plastic film are placed in the mould of the press, one on the bottom, the other on the top. A punched-out sheet of paper, printed on one side only, is then placed over each of the sheets of film. The middle of the sandwich is then filled with a layer of heated vinyl granulates. The layers are fused together in the machine under heat and pressure" [Peter Bastine: Extraordinary Records, Taschen, Cologne, 2009]. Rainer -- Dr. Rainer E. Lotz Rotdornweg 81 53177 Bonn (Germany) Tel: 0049-228-352808 Fax: 0049-228-365142 Web: www.lotz-verlag.de