Skeletal Quartz/Fenster Quartz Crystals #4 weigh 15.1 to 20.0 grams. Most of these crystals are water clear. Some of these have imperfections, and a few of them have inclusions. Please let me pick one for you. These are $3.50 USD each.
(Healing Crystal, Ascension Crystal)
Hardness: 7.0
Origin: Mexico
Skeletal Quartz/Fenster Quartz is another specialty Quartz formation. On a face of the crystal, a "window" will form, leaving the center of the crystal with just air, and this is right underneath the crystal face. So you have a solid crystal face with a "window" of sorts underneath it; a skeleton structure. They're very unusual-looking formations. Sometimes the window opens to the outside of the crystal.