Bhasma are equivalent to calx, which are prepared by a process of calcination. Bhasma are made by calcination the given drugs, which may either be organic or inorganic in origin.The materials which are made into Bhasma in from, minerals to metals, and animal to plant products. Chemically, the bhasma are oxides or ashes of the drug concerned, in state of fine division, with a certain proportion of these particles in the colloidal dimensions.
The following equipments are required for the preparation of bhasma:-
1. The necessary drugs.
2. Mortar and pestle.
3. Long cloth ribbon and some wet clay.
4. Two shallow earthern discs of identical dimensions.
5. Cow dung cake- sufficient numbers.
6. Cloth of fine mesh.
7. Vessels to prepare and handle juices and decoctions.
8. Spatulae of small size for handling the bhasma.
Notes on the Drugs used
1. The drugs should be purified according to the convention of Ayurvedic science and then only takers for use in medicine.
2. The material taken should be properly identified.
3. Great care should be exercised when plunging or pouring a heated metal into a fluid for purification so that the splashing liquid or metal may not cause injury.
Method of Preparation of Bhasma
The material which is to be made into bhasma is cleaned and purified according to the method prescribed for that material. This purification process is very important in that the poisonous organic and inorganic drugs are rendered fit for medicinal use. The purification processes consist mainly of soaking, boiling or grinding the drugs in specific fluids such as juices of green drugs or decoctions of dry drugs. Sometimes, the metals are heated or melted and suddenly plunged or poured in some oils or infusions. Care
should be taken to protect oneself from being injured in any way when handling molten or heated metals.
When the drugs are purified and ground with the prescribed infusions, they are made into small circular cakes and dried. When dry. Thev are taken for calcination.
The materials ready for calcination are put into the crucible and Sealed with the clay ribbon. The material is placed inside a disc and then the other disc is inverted over it and the set up. Is sealed around the rim with the clay smeared cloth ribbon. This makes a “capsule” type crucible. The seal is allowed to dry and when it is completely dried the crucible is taken and placed in the kiln for calcination.
The kiln or ‘Puta’ as it is called in sanskrit, is made up of digging a pit in the soil and filing it with dry cow dung cakes as fuel. The size of the pit depends upon the number of cow dung cakes used per operation. The cow dung cakes of fair size, are circular discs with a diameter of about 10” and a thickness of ¾”. (It is better that the interior of the kiln is constructed with bricks).
75% of the prescribed number of cow dung cakes are arranged in the pit and then the sealed crucible is placed in the centre. The rest of the dung calces are arranged over the capsule. The top of the heap of cow dung cakes should be in the form of a dome, so that when the top is seton fire, it will spread evenly in all directions.
The kiln will be burning for a long time until all the dung cakes are converted into ashes. When the kiln is cooled down. The ashes are care fully removed and the crucible is taken out with out damaging the seal. Then the exterior is cleaned and the seal is scraped off. The material kept inside would have been calcined and it is collected.
For the complete transformation of the material into the bhasma state, this process of calcination may have to be repeated a number of times or as many times as directed in the recipe. However the calcination is repeated until a satisfactory product is obtained in most of the preparations. But where a recipe reads that the calcination should be repeated for a particular number of times, the process is usually repeated so many times as prescribed even if a satisfactory bhasma is obtained within a few repetitions.
All the bhasma are in the form of extremely fine powders when properly prepared.
While preparing the bhasma of Lead, Tin and Zinc the number of cow dung cakes used, should always be comparatively lesser than the number used for other metals because exessive heating will result in the reversal of the bhasma into metallic state.
Test for Complete Calcination
To test whether the given material has been completely Calcined, several tests are in use.
1. Different materials attain specific shades of color when completely calcined. This color change could be learnt only by experience.
2. A pinch of bhasma gently put on water, floats on the surface, if it is fully calcined (Varitharanam).
3. A pinch of bhasma put gently on water and floats on the surface even if a horse gram is placed on it (Hamsa- Vaththarana). The method is also known by the name “Uththarna”.
4. When a pinch of bhasma is taken and pressed between fingers, it shows clear impressions of finger prints and the Particles of bhasma will be seen in the furrows of the prints (Rekha poornatha).
5. When a bhasma is satisfactorily prepared, it is irreversible to its metallic or original form when heated with a mixture of (1) Cane jaggery (2) Hemp leaf powder. (3) Bdellium or Borax (4) Ghee and (5) Honey. (Apunarbhava).
6. The product obtained as a result of the above test (Apunarbhava bhasma) is once again melted with a small quantity of silver in a crucible by means of a blower. The apunarbhava bhasma if properly calcined will not combine with the silver and remain as such. (Niruththam).
Storage of Bhasma
Bhasma are stored in glass bottles usually. For smaller packings, vials of glass or plastics could be used. Capsule packing could also be done when equipment is available. The medicines should always be relevantly labelled.