During His visit to east, Guru Nanak Dev Ji reached the place of Gurdwara Gau Ghat (Gae Ghat) outside Patna city. On request of Bhai Mardana Ji, Guru Ji gave him a laal, a precious stone.
Bhai Mardana went to Patna city to sell the laal. He reached Sunar Toli market. Sunar means a gold merchant. A sunar named Murli Dhar took Bhai Mardana to Salas Rai Johri. Salas Rai was so amazed to see such a precious stone that he bowed before the stone and presented Rs 100 as darshan bheta (the money presented or gifted for viewing a thing).
Bhai Mardana took that money to Guru Ji. Guru Ji returned the gifted money back and said this money cannot be accepted because we haven’t sold the laal yet. Later, Salas Rai visited Gau Ghat to see Guru Nanak Sahib Ji. Guru Ji advised him that the way he recognised the value of the precious laal, he should also recognise the value of precious life, which was useless without remembering God. After listening to the teaching of Guru Ji, Salas Rai became His follower. Murlidhar also became follower of Guru Ji.
On the request of Murildhar, Guru Ji came to the place of Sunar Toli. Satsang was started there. This place is known as Gurdwara Sunar Toli.
Guru Ji also visited the home of Salas Rai Johri. This blessed home of Salas Rai is the place where, later, Guru Gobind Singh Ji took birth in 1666 AD. It is the place where main Gurdwara Patna Sahib is situated.
Gurdwara Sunar Toli had very small space, later Mata Sudesh Kumar Arora and her family gifted their home adjoining the Gurdwara. This gurdwara is in the west of Takht Sahib. It takes 10 minutes to reach there on foot from Takht Sahib.
— This is translation of history written in Hindi on a board installed by Baba Harbans Singh Ji, Kar Seva Delhi Wale at Gurdwara Sunar Toli.