There are five things which are impure yet pure.

1. Uchhishta — Cow’s milk.
The cow’s calf first drinks the cow’s milk and then discards it. Nevertheless, it is sacred and offered to Lord Shiva.

2. Shiva Nirmalya —
Water of the Ganges
The Ganges descended from heaven directly onto the head of Lord Shiva. According to tradition, everything offered to Lord Shiva is called Nirmalya, but Ganga water is sacred.

3. Vamanam—
Vomiting—Honey.
When a bee returns to its hive with nectar from flowers, it vomits the nectar from its mouth in the form of honey, which is used in sacred ceremonies.

4. Shava Karpatam—Silk Cloth
Purity is required for religious activities, and silk cloth is considered sacred. However, to make silk, the silkworm is immersed in boiling water and dies. The silk obtained is then considered a Shava Karpat, yet it is still sacred.

5. Crow droppings—Crow feces
Crows eat the fruit of peepal trees and leave their seeds in their droppings, which then give rise to new trees. You may have noticed that peepal trees do not grow anywhere, but rather, peepal trees grow from crow droppings, yet they are sacred.