Microwave Digestion and Block Digestion are both sample preparation techniques used in analytical chemistry, particularly for trace metal analysis and elemental analysis.

Microwave Digestion uses microwave energy to rapidly heat samples in a closed vessel with strong acids and high temperatures and pressures, commonly used for ICP-MS, ICP-OES, and atomic absorption spectroscopy, while Block Digestion uses a heated block to slowly digest samples in open vessels and operates at lower temperatures compared to microwave digestion, often used for environmental and food sample preparation.