Long Jaafar has been historically credited with the discovery of tin in Larut in 1848. According to legend, Long Jaafar had an elephant named Larut and he used to take this elephant with him when journeying between Bukit Gantang and Lubok Merbau. One day the elephant went missing and when the elephant was eventually found three days later Long Jaafar noticed tin ore embedded in the mud that was on the elephant’s legs. It is said that this was how Larut got its name.
Eventually in 1850, Larut district was bestowed upon Long Jaafar by Raja Muda Ngah Ali and the Chiefs of Perak: the Temenggong, Panglima Bukit Gantang, Panglima Kinta, Syahbandar and Seri Adika Raja. Some time later, the Sultan of Perak, Sultan Abdullah, died in 1857 and a series of succession disputes ensued. Unhappy with the abuse and favouritism of various royalties, rival Malay camps took sides with one or the other of the two great Chinese secret societies present in there at the time.
Long Jaafar established and developed his administrative centre at Bukit Gantang and made Kuala Sungai Limau at Trong the principal harbour of the Larut Settlement. In 1857 Long Jaafar was succeeded by his son Ngah Ibrahim.