Washermen, Potters, Goldsmiths, Oil-pressures are known as:

Service Castes

Agriculture is the single most important source of livelihood for the majority of the rural population. But the rural is not just agriculture. Many activities that support agriculture and village life are also sources of livelihood for people in rural India. For example, a large number of artisans such as potters, carpenters, weavers, ironsmiths, and goldsmiths are found in rural areas. They were once part and parcel of the village economy. Their numbers have been steadily lessening since the colonial period. 

Rural life also supported many other specialists and crafts persons as storytellers, astrologers, priests, water-distributors, and oil-pressers. The diversity of occupations in rural India was reflected in the caste system, which in most regions included specialist and ‘service’ castes such as Washermen, Potters, and Goldsmiths.