Denim Jeans looks like it has a purple hue to it. However, it is definantely more towards dark blue Jean colour than purple looking.  The camera is picking up of the base dye as it has a purple/blue undertone.  A tiny amount of black dye has been added to bring out the blue. 
Hand dyed onto a 4ply base yarn of 85% merino plus 15% silk, gives this yarn a delicious soft silky feel with a beautiful luster and soft drape especially to shawls and wraps.
Each hank is approx 100gms/400m.
Recommended needles 2.25mm- 3.25mm.
This is a gentle machine washable yarn in cool to warm water.  Dry flat and in the shade to maintain colour.  Always store your precious hand made items rolled or flat to maintain shape and size.