The miner’s finances have come under strain from rising inflation and low prices amid political instability in South Africa, despite an improved trading performance.
Its plans to “support a sustainable business” include selling excess processing capacity of up to 500,000 platinum ounces a year.
It will also consider funding partners.
Lonmin said in a statement: “It is too early to…define the ultimate effect of the operational review on the company, but the overall aim remains for the business to [be] cash positive after capital investment.”
The company is seeking to reduce annual overhead costs by at least 500 million rand (£29 million) by the end of the year to September 30, 2018.
Matt Hasson on Numis Securities said: “Whilst Lonmin has made improvements to its capital structure, production and operating cost profile through its restructuring, further cash preserving measures are clearly needed.
“We view the given steps as logical, though finding joint venture partners or buyers may not be easy given the headwinds facing the South African platinum mining operations.”
Shares rose 4¾p to 93¾p.