The Imperial German Colonial Medal (Kolonialdenkmünze) was established by Kaiser Wilhelm II on 13 June 1912 with revisions on 17 February 1914.  The medal with clasps was awarded retroactively.  This guide will address only the various ribbons.  Copies and forgeries are known.  

• Pre-WWI Contemporary  Ribbon:  Silk, the weave is 16 rows per cm, each thread is 2 strands of ca. 10-12 fibers per strand, and it is UV-negative.  Silk, the weave is 16-17 rows per cm, each thread is 2 strands of ca. 10 fibers per strand, and it is UV-negative. 
• WWI-era Replacement Ribbon:  Silk, the weave is 15 rows per cm, each thread is 2 strands of ca. 20 fibers per strand, and it is UV-negative.  Silk, the weave is 16 rows per cm, each thread is 2 strands of ca. 15 fibers per strand, and it is UV-negative. 
• WWII-era Replacement Ribbon: Silk, the weave is 15 rows per cm, each thread is 2 strands of ca. 15 fibers per strand, and it is UV-negative.  Cotton, the weave is 14 rows per cm, each thread is 2 strands of ca. 10-12 fibers per strand, and it is UV-negative. 
• Modern-era Replacement Ribbon: Often found in widths of exactly 3.00cm or 3.10cm.  Silk, the weave is 14 rows per cm, each thread is 3 strands of ca. 10 fibers per strand, and it is UV-negative.  Cotton, the weave is 13 rows per cm, each thread is 2 strands of ca. 15 fibers per strand, and it is UV-negative.  Poly, the thread melts and clumps when burned, the weave is 15 rows per cm, each thread is 2 strands of ca. 10 fibers per strand, and it is UV-positive.  Cotton, the weave is 14 rows per cm, each thread is 3 strands of ca. 8-10 fibers per strand, and it is a false UV-positive due to the use of a fabric finish. Poly-cotton mix, the weave is 14-15 rows per cm, each thread is 2 strands of ca. 10-15 fibers per strand, and it is UV-positive.  

 My best advice is:  Buy only from a reputable dealer who specializes in Imperial German medals and who will offer you a 100% guarantee.

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