Many people with Ehlers-Danlos syndrome have soft, velvety skin that is highly stretchy (elastic) and fragile. Affected individuals tend to bruise easily, and some types of the condition also cause abnormal scarring.
Quartzite is a metamorphic rock that is formed from the sedimentary rock sandstone. Slate is a metamorphic rock that is formed from the sedimentary rock mudstone. Granulite is a metamorphic rock that is formed from the igneous rock basalt.
The metamorphic versions of other sedimentary rocks like sandstone and shale are well known, at least to home renovators. Quartzite kitchen benches were once sandstone, and slate tiles are the pressure-cooked version of shale.