These look like hieroglyphs inscribed on their faces. For meditating, it can take you back to ancient civilizations to access wisdom and knowledge of one's past lives. These crystals are known to be useful in attuning to spiritual training and initiations carried out at the time- reawakening skills and one's healing abilities.
Etched crystals are said to be personal crystals (used by one person only). Yet, cleansed properly and reprogrammed, it can guide another soul consciously to access their own past knowledge.
