While Cedar Canyon (who is not the manufacturer of Shiva Paintstiks) may not refer to them as oil sticks, that is how they are classified by art supply stores and how they were developed in the 1960's...as an alternative form of oil paints for artists. They blend with tube oils and can be thinned/cleaned up with turp just like any other oil paint. They are oil color, the same as tube oils...and that's a direct quote from the maker.
For an independent article on Paintstiks and fabric
http://www.lauramurraydesigns.com/paint-chem.php
For product details from the manufacturer
http://www.richesonart.com/pdfs/shivapaintstiks.pdf
For an excellent art supply retailer with great prices (also has a video)
http://www.dickblick.com/products/sh...ntstik-colors/