Crystal growth in solution under static conditions

A method of preparing a crystal based on a compound (C), by crystal growth in solution, the method comprising:

• providing a crystallization system comprising:
• a solution (S) supersaturated with said compound (C),
• a crystallization chamber, in fluid communication with
• a saturation chamber, said saturation chamber including a source of compound (C) in the form of a feeder substance;
• maintaining a constant crystallization temperature (Tc) in the crystallization chamber and a constant saturation temperature (Ts) in the saturation chamber, wherein Tc is different from Ts and the solubility of the compound (C) in the solution (S) at the temperature Ts is greater than the solubility of the compound (C) in the solution (S) at the temperature Tc;
• circulating solution (S) in a continuous flow circuit between the saturation chamber and the crystallization chamber, wherein the solution is circulated at a substantially constant flow rate;
• and
• carrying out the crystal growth within the crystallization chamber, while maintaining the constant crystallization temperature Tc, the constant saturation temperature Ts, and the substantially constant flow rate, in order to maintain a constant rate of supersaturation within the crystallization chamber during the crystal growth.