Question: what are the strongest crystals?
Answer: Clear Quartz. Clear quartz, also called rock crystal, is known as a master healer and a stone of great power. ... 
Ruby. The ruby is said to be the most powerful gem in the universe because of its high energy. ... 
Amethyst. Amethyst is a very powerful stone for master healers and meditators. ... 
Malachite. ... 
Aventurine. ... 
Citrine. ... 
Kunzite.