Assertion: Lichen is important for chemical industries.
Reason: Litmus and Orcein are formed from lichens.

Both Assertion (A) and Reason (R) are correct.

Lichens are indeed important for chemical industries, particularly in the production of dyes such as litmus and orcein.

Litmus is a natural dye derived from lichens, specifically from certain species of Roccella and Dendrographa. Litmus is used as an acid-base indicator in various chemical applications, such as laboratory experiments and the manufacturing of pH test papers. It changes color in response to the acidity or alkalinity of a solution, making it a valuable tool in chemical analysis.

Orcein is another dye derived from lichens, particularly from species of Roccella and Ochrolechia. It is commonly used in histology and microscopy to stain biological samples, such as tissue sections, for microscopic examination. Orcein is also utilized in the production of certain textile dyes.

These dyes, litmus and orcein, have been traditionally extracted from lichens due to the presence of specific compounds within the lichen thallus that impart the characteristic colors. The extraction and utilization of these dyes have been important for various chemical industries and scientific applications.

In conclusion, the assertion that lichen is important for chemical industries is correct, and the reason provided, stating that litmus and orcein are formed from lichens, is accurate.