Skein of white artificial silk thread. It has a paper label in German stating: KUNSTSEIDE-FILET-HÄKELGARN ELFI nr. 5 Farbe 501 plus other information including Alwo VEB alwo Altenburger Wollspinnerei.
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The design used for the curtains is based on medieval European forms associated with the late 19th century Arts and Crafts Movement.