The medium on which the maps are printed is probably "stone paper", see https://en.wikipedia.org/wiki/Stone_paper. I received some 6 maps at the of 2016, printed on this material. Because it felt so strangely felt-like it made me very curious. According to the publishing firm it does not contain paper, i.e. cellulose or wood-pulp etc., but is made of a mixture of 80% calcium carbonate and 20% tree-resin, and is rip and waterproof. (https://www.kaartenenatlassen.nl/vouwkaarten/topografische-kaarten/topografische-kaart-zuid-limburg-geuldal In the Dutch text it is mentioned that the map is printed on environmental-friendly stone paper) 

According to its nature it is 'natural' and falls outside all categories known up till now. So a new code may be necessary.

Jan Smits
Koninklijke Bibliotheek, National Library of The Netherlands

-----Oorspronkelijk bericht-----
Van: Maps-L: Map Librarians, etc. [mailto:[log in to unmask]] Namens Curtis, Gwen
Verzonden: donderdag 16 februari 2017 21:11
Aan: [log in to unmask]
Onderwerp: Waterproof maps

I recently received a number of Reise Know-How road maps that are described as "rip and waterproof."  I've seen these described in various records as plastic, plastic-coated, and synthetic.  The 007 field for maps gives the option of synthetic, plastic, and vinyl.  Can anyone give me an idea as to what type of material these actually are and what the 007 should be?

Gwen Curtis
Map Collection
410C Science and Engineering Library
University of Kentucky Libraries
Lexington, KY 40506-0039

(859) 257-1853
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