Preparation of the ,,white stones“.
1. Make friends with your butcher! Take the middle third of a cow‘s thigh bone. Using a butcher‘s saw, saw it into pieces (size approx. 4cm x 1.5cm).
2. Remove the bone marrow.
3. Bring the pieces of bone to the boil in water.
4. Bring to the boil again using fresh water containing soap, e.g. Omo. NaOH is even better than soap. This is to remove the grease.
5. Repeat step 4.
6. Boil once again in fresh water to remove the soap.
7. Dry in the sun for 5 days or in the solar oven for 1 day.
The stones should now look like ivory
Preparation of the ,,black stones“
1. Wrap each piece in 2 or 3 layers of aluminium foil.
2. Place the pieces in the red, glowing centre of a charcoal fire, and cover with a little pounded charcoal. Depending on the heat of the fire and the size of the stones, this process may take as little as ten minutes or as long as two hours.
3. It takes some skill and experience to be able to judge when they are ready. A good rule of thumb is to wait until the (very unpleasant) smell disappears. Then check one piece, taking great care not to burn your fingers. The stone should be black and firm. If it is very brown, it is not yet ready, if on the other hand there is white dust, it has already been heated for too long and has started to oxidize and disintegrate.
4. Take all the stones from the fire and place them in a closed container to prevent them from oxidizing as they cool.
5. Use a file to take away any rough edges.
Care of the ,,black stone“
Handle the ,,black stone“ with great care. Protect it from dust, and keep it completely dry. Store it in an air-tight container such as those used for films.
Regeneration of ,,black stones“
1. Boil in soapy water for 10 minutes. Do not throw it into boiling water nor expose to quick changes in temperature, or the labyrinth inside the stone which absorbs the liquids will be destroyed.
2. Boil in fresh water for 10 minutes.
3. Dry in the solar oven.
Uses of the ,,black stone“
1. Boils, small abscesses and infected wounds: Break the black stone to the size of the boil. Press it onto the boil/abscess to make contact with the liquid. The black stone empties the boil, thus mechanically removing most of the of germs. To make your black stone smaller, place it in a plastic bag, cover it with a cloth and strike it with a hammer.
2. Snakebites and bites of poisonous insects, e.g. scorpions: Press onto the wound to make contact with the liquid. As soon as the stone contacts the blood, it sucks itself tight to the wound and does not let go until all the poison and secretion has been absorbed. This may take as long as a day.
A black stone is, therefore, an essential component of every tropical first aid kit!
How does the black stone work?
It contains a myriad of tiny passages. Through the process of capillary action, a pressure below atmospheric pressure is created an the wound, as a result of which the black stone sticks firmly to the affected area until it has absorbed its maximum capacity of liquid. Just like a sponge in water!