To prepare Madhyama Kshara, One or one and a half Kudava (approximately 240 ml) of Ksharaodaka should be reserved for later use in the preparation process. Take the remaining Ksharaodaka and place it on fire to evaporate excess moisture. Simultaneously, gather Katasharkara, Bhasmasharkara, Shukti, and Shankha Nabhi. Heat these ingredients until they become red hot. Once the dravyas are red hot, immediately dip them into the reserved Ksharaodaka. After dipping, powder the mixture in the same Ksharaodaka. Transfer the powdered mixture into an iron vessel. Cook this mixture while continuously stirring until it achieves a consistency that is neither too thick nor too thin. So thus madyama kshara is prepared.
Now in the contemporary method, after the filtrate is boiled and reduced to ⅓, then we add 50 g of shukti churna which is commercially available (Ca(OH)2) to the portion and boil again. This solution is filtered using cotton cloth to remove the crystals of powder and heated again. Continue boiling till it becomes neither too thick nor too thin. This portion is called madyama kshara.
Preparation of madyama kshara is basically increasing therapeutic efficacy. So as we boil the filtrate, excess moisture is removed and this concentrates the solution. And then adding the mixture of bhasma sharkara, shukti etc as mentioned in shastras, medicinal qualities are being activated. By adding this in ksharodaka, ensures that the medicinal properties are evenly distributed throughout the solution.
The inclusion of calcium ore in the preparation of Madhyama Kshara is a strategic choice that enhances its alkaline properties, promotes beneficial chemical reactions, and improves its therapeutic potential. Calcium ore, which includes substances like limestone or conch shell ash, is rich in calcium carbonate. When added to the Kshara preparation, it increases the alkaline nature of the final product. Various ores of calcium mostly contain 95% calcium carbonate and 5% calcium phosphate, magnesium carbonate and microelements. Nowadays, we commonly add shukti churna which is Ca(OH)2 [calcium hydroxide] as it is commercially available. Instead of this we can also use other calcium ores which are basically CaCO3 predominant.