Largest crystal?

The world’s largest fast-growth crystal, weighing in at 701 pounds, has been grown by researchers at the US Dept of Energy’s Lawrence Livermore National Laboratory.The pyramid-shaped KDP (potassium dihydrogen phosphate) crystal measures approximately 26 inches by 21 inches by 23 inches high. It was grown in a record 52 days using a special rapid-growth technique developed in Russia and advanced at Lawrence Livermore by Nataalia Zaitseva and Ruth Hawley-Fedder.