BHP Billiton was formed from two large mineral resource companies: the Australian Broken Hill Proprietary Company Limited and the Anglo-Dutch Billiton plc.
The new logo was a literal metaphor for the merger of the two companies, presented as a set of two metallic blobs periodically merging creating a new entity. The logo at the time cost around $800,000 to produce at the time. While this icon's meaning overtime has become more moot, it still is one of the most prominent and recognisable symbols of the mining business.
In May 2017, the Billiton part of the BHP Billiton name was dropped and the company in an campaign to promote the company as a staple of the Australian economy. A new campaign was launched along with a new tagline- "Think Big".