The mineralization of crystalline inorganic components in Japanese serow horn

The Japanese serow (Capricornis crispus) is protected as a special natural monument in Japan. The ring count of the soft X-ray photographs of Japanese serow horn was found to be a useful criteria to determine the ages exactly. The mineralization process in Japanese serow horn was examined microscopic, ICP and X-ray diffraction methods. The incremental lines appeared as light and dark layers in the section stained for fuchsin and methylen blue. Mineral depositions were observed among the keratin fibers, no matrix vesicle in the electron dense regions. X-ray diffraction pattern of crystalline inorganic components in Japanese serow horn was determined as beta-tricalcium phosphate (TCP), hydroxyapatite (HA) and unknown phase. ICP measurement was also carried out. The horn contained trace elements of K besides Na, Ca, Fe and P. The Ca/P molar was found to be 2.9. The ratio was much higher than the theoretical value of HA. Presumably, keratin was the seed which might be related to mineralization and higher Ca activity was detected in the initial phase of epitaxial growth. Analytical results of the measurement of trace elements in Japanese serow horn by using ICP method seemed to be correlated with the evaluation of environmental conditions. The present study indicated that the mineralization of Japanese serow horn directly related with deposition Ca-deficient HA among the keratin fibers.