Aqueous ball milling of nacre constituents facilitates · The ball mill MiniCer Netzsch Germany was cleaned with HNO 3 and NaClO followed by intensive washing with ultrapure water Wet grinding was performed at 28°C and 3000 using ZrO 2 balls 300 µm in diameter 180 g Prior to ball milling the amount of nacre tablets and geological aragonite was reduced to 15 wt% with ultrapure water