done and dusted

What is the origin of the idiom "done and dusted" and when to use it?

The exact origin of the idiom "done and dusted" is unclear, but it is believed to have originated in Britain during the 19th century. The phrase likely draws from the practice of cleaning or tidying up after completing a task. When a task was finished, dust or dirt would be removed, ensuring that everything was clean and tidy. Over time, the expression "done and dusted" became a figurative way of conveying the completion or finalization of various activities or events. Its usage has since spread beyond Britain and is now a commonly used idiom in English-speaking countries to signify the successful completion of a task or activity.