I thought that it may affect the clotting time of blood. Maybe simple blood clotting test could be done.. and clean it with lime juice afterwards? To check if the blackened part of the blade may really affect the color and clotting time of blood. But I'm not sure whether it could be completely cleaned from the blade or not, that's why I'm still hesitating.
By the way, the kris is obtained in Pagaralam, South Sumatra. Not from other province
