Vijay Surwade may have worked as a bank manager by day — but for five decades he spent his evenings building one of the world's biggest archives dedicated to India's pioneering Dalit rights campaigner B.R. Ambedkar.

His collection includes everything from documents and photos to Ambedkar's broken spectacles and dentures, all housed in shoe boxes and concertina files in Surwade's apartment in the western city of Kalyan, about 45 kilometers northeast of Mumbai.

It is among a number of informal archives collected by ordinary Dalit people who say their stories otherwise risk being lost, undermining their cultures and the fight against caste-based discrimination.