Can India's 5,000-Year-Old Disposable Clay Cups Compete With Plastic?

A kulhad is a biodegradable, disposable clay cup used in India by food vendors to serve hot beverages like chai and some desserts like yogurt. The cups have been excavated from the Indus Valley as far back as the end of the Stone Age, 5,000 years ago. They are generally unglazed and unpainted, so …