Oil pastels tend to be a bit of the black sheep of mediums, with many of us not really knowing what to with them and feeling uncomfortable at the thought. I've been using them most recently for mixed media, and to love the way you can combine blended color with line, and build up 'complicated colors' through layering, without having the dust of soft pastels.
At the most basic, I think there are three mark-making techniques: line, blocked-in color, and blended....
Iridescent Oil Pastels as a Painting Background
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