A gelatin size (coating) prevents the unhardened dichromate from permeating the paper fibers. The unhardened bitumen was then dissolved away. The laser hardens the spots that it touches and leaves the rest unhardened. It is then soaked in warm water to dissolve the unhardened portion of the gelatin. The tissue is then developed by treatment with warm water, which dissolves the unhardened gelatin. Unhardened 5086 has a yield strength of and ultimate tensile strength of from . Unhardened 5059 has a yield strength of and ultimate tensile strength of from . Soft jaws are made of soft materials such as soft (unhardened) metal, plastic, or wood. The unhardened fraction was then washed away. There are also three campsites on unhardened ground, each with a fire ring and grate. Damage can be catastrophic if "unhardened" seedlings are exposed to frost. The unhardened material is then dissolved to produce a "shell". The unhardened part was then rinsed away with a solvent.