What are the two types of tanning (al-Dibaghah) recognized in the text to purify carcass hides?

Purification of Hides (الدباغة) & Special Substances (Musk, Civet)

• Industrial tanning and Domestic tanning.
• Real/Chemical tanning (Haqīqiyyah) and Ruling/Natural tanning (Hukmiyyah).
• Water tanning and Earth tanning.
• Hot tanning and Cold tanning.