Turns out in India, finders are not keepers straight away.
Any jewelry or precious item dug out from earth is legally termed as "treasure" and is governed by the Indian Treasure Trove Act of 1878. (yes, 1800s. I know we are in 21st century but do governed by rules from 19th century :) )
Under section 4 of the Act, the finder of a "treasure" is supposed to inform the district revenue officer either on his/her own or on receiving a notice from the government.
The finder is also required to deposit the find either with the district revenue officials or undertake to produce it before authorities when required.All, is not lost though -
As per section 11 of the Act, the finder of a treasure, however, still has a chance of owning it if authorities decide after an enquiry that it belongs to none else.