Chang On Siew 鄭安秀

Chang On Siew or also known as Chan On Siew was a well-known tin miner in Lahat, Perak, born in China to Chang Kwei Long. Chang Kwei Long first came to Penang in the early 1850s and had worked in various interests before landed in tin mining. Thirty years later, he had been a well-established man where he sponsored his son Chang On Siew to Perak.

Chang On Siew first lived at Menglembu and then to Lahat. He was the owner of the Rotan Dahan Mines at Pengkalan Kacha, where more than 400 men were employed in the mining operations. His mines at Lahat were managed by a European Engineer, A. Hamilton.

His story in the Katcha mines was intriguing and worth to-be-told. The tin deposit in Katcha was rich, but due to its location near hilly areas, many miners were disinterested to develop it, because it was difficult in installing water supply to the mines. Chang On Siew was the first miner credited for his successful method of working alluvial hill land. He first solved the problem by installing water tank on top of the hill by using water pumps. The water from the peak will be channelled downhill, but this will cause ponding. So water will then re-pump again up to the peak to avoid ponding. This repetitive circular process is called hydraulic mining method. Something that, Chang On Siew discovered without knowing about it.

Besides tin mines, Chang On Siew who had shares in several mining companies also ventured into rubber plantations. One of his rubber estates at Kota Bahru was about 3,000 acres. In 1905, the price of rubber hiked to 6s 4d per pound making a significant modal return to rubber investors. In 1906, Chang On Siew sold his Kota Bahru Estate to an English company. Shortly afterwards, in 1908, the international commodity price for tin went down seriously and many miners suffered substantial loss. However, Chang On Siew who had sold off his rubber estate was able to secure his mines from the crisis. He was then known as a wise investor. His eldest and third sons, Chang Mook Yen and Chang Sen Yan took charge of his business in Malaya while his second son Chang Tey Yan managed the business in China.