PPT Slide
Skeletal quartz (also known as elestial quartz) exhibits a layered or ribbed pattern. Its appearance gave rise to the term "skeletal" as the crystals resemble what someone with a good imagination would expect the skeleton of a quartz crystal to look like (not that they exist). The patterns exhibited by skeletal quartz represent internal and external dissolution-growth features resulting from unstable conditions during crystallization. At the time that the crystals were forming, the conditions were such that the crystals would alternate between growing and dissolving. This "two-step forward and one-step backward" process resulted in the unusual step-like appearance.