Bone decalcification is the removal of calcium ions from the bone through histological process thereby making the bone flexible and easy for pathological investigation.

This is necessary in order to obtain soft sections of the bone using the microtome. Every thin section cut can be processed like any other soft tissue of the body. It should be noted that calcium ions found in the bones are responsible for its rigid posture, people suffering from diseases like osteomalacia and rickets have an unusually low amounts of calcium ions in their bones thereby rendering their bones flexible and most times unable to carry their body weight.There to two categories of decalcifying agenting namely, chelating agents and acids. The acids are further divided into weak (picric,acetic and formic acid)and strong acids (nitric and hydrochloric acid).The acids make up a solution of calcium ions while the chelating agents take up the calcium ions. mostly used chelating agent is EDTA. Acids have some effects on the stainability of the tissue.