Silas Aaron Hardoon was another agent of the Sassoons who you could say founded modern China and India.

He made his money from property, Wiki and other online sources do not mention the exact details though.

Hardoon bought land for pennies on the sides the Nanking road in Shanghai, he then convinced the governor to collect money for the pavement of that road. After the road was paved the land value shot up and he become what can be described in today's money a billionaire.

The Wiki and online sources make it sound as if he put his own money to pave the road which he didn't. Age old use of subsidies through controlling the government.

Quote from here: https://www.historic-shanghai.com/inside-hardoons-garden/

"How savvy he was! How he began investing himself — in real estate, opium, and guanxi. The real estate he owned—the length of Nanjing Road! Sprawling lilongs!

How eccentric he was! Collecting rent from his tenants himself, and sitting bundled up in an overcoat in his unheated office to save a few pennies."