Abstract: There are some low-price calci-corals,which have some similar characteristics to the red corals and are not used as jewelry materials,are found in the market recently.To distinguish these low-price coral samples from the precious red coral samples,the biological classification is investigated from the biological angle.The characteristics of structure,treatment and market features of the low-price calci-coral samples are analysed by using polarizing microscope,magnification observation and conventional gemmological test.The results show that the species of the low-price calci-coral samples are different from that of the red coral samples.They have the different biological characteristics and appearance structure,gemmological parameters and Raman spectrum,appearing on the jewelry market after treatment.They could be identified by the conventional gemmological examination and the measurement of Raman spectrum.