Materials for sprang
You can use a lot of different materials for sprang, but.... not everything is easy to work with. If you just start spranging, it is nice to start with a smooth firm yarn, with a little bit of elasticity. A cotton crochet yarn is nice to learn the technique. Fluffy or furry yarn, mohair and yarn with a lot of elasticity are not advisable. They are very difficult to work with.  However sometimes I do want these difficult yarns in my sprang. One way I can use them is crocheting around XL ribbon yarn.

The picture below shows some cords that are made by crocheting around XL ribbon yarn.