[Determination of densities of mineral drugs and their calcined products by sealing wax densimetry].

Objective: To determine densities of mineral drugs and their calcined products by using sealing wax densimetry, and to establish the testing method of crispness for calcined traditional Chinese medicine.

Method: Taking density as detection indicator, the accuracies of mineral drugs and their calcined products were investigated by sealing wax densimetry compared with direct densimetry, and the method of density determination was optimized.

Result: The density values measured by two methods investigated above were significantly different (P < 0.01), the density values of Pyritum, Haematitum, calcined Pyritum and calcined Haematitum measured by direct densimetry were increased 1.66%, 9.43%, 96.72% and 9.02%, respectively compared with that measured by sealing wax densimetry.

Conclusion: Sealing wax densimetry is suitable for the density determination of mineral drugs and their calcined products with its high accuracy, whereas direct densimetry'is not suitable for the density determination of mineral drugs and their calcined products.