A Móra Ferenc Múzeum Évkönyve, 1969. 2. (Szeged, 1969)

Kiszely, István: Derivatographic Research of Subfossile Bones

(rough) bones the lines showing reactions are disturbed over 420° С owing to the mechanical change (scaling) of the bone. As regards compactness: greatly compacted and loose bone -give exactly the same changes in quantity (TG), the DTA curves of the compacted bone are, however, much more explicit. Concerning choosing of time: 100 minutes proved optimal; less time is not enough for the bone-powder, having bad heat conduction, to behave consistently, longer time (e. g. 800 minutes), though optimal, needs too much time and owing to this is more expensive. The reactions are rich in details and appear at the degree of heat where the physical-chemical reactions take place. Concerning the crucible: platinum crucible gives about twolfold effects opposed to corundum. The process of the reactions is also more expressed. DECAICINATEO BONE 0,П47 mj AC. VI

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" CENTURY Fig. 3. Derivatogramm of decalcinated bones. The change of the numerous organic materials induced by a fine heat effect isn't oppressed by the change of the inorganic component of great mass. The derivatographical analysis of decalcinated bone has been made by the author. Only organic substance of a bone unit (1 gr) was studied. (Fig. 3.) In this case considerably more changes under heat effect have been found. It has to be taken into consideration whether it worth while to work out the derivatography of the „organic substance" only, because changes of the greater quantities of inorganic substances, evoked by heat, inhibit the more delicious changes. In think the answer to this question must be no; 1. because decalcination can never be complete, the decalcinator does not only damage the substance but it brings foreign substances into the bone, too; 2. because the inorganic 221