* Lonmin says rights issue must be backed if company tosurvive
* Company could go under between December and May 2016 (Adds analyst comment, detail)
By Zandi Shabalala
JOHANNESBURG, Nov 4 (Reuters) - Lonmin ,world's No.3 platinum miner, urged shareholders to approve a$400 million equity cash call at a meeting next week, saying ina document posted on its website the injection was crucial toits survival.
Lonmin's shares in London fell 6.8 percent to 23.93 pence by1223 GMT. The Johannesburg-listed stock was down by 8 percent at5.00 rand.
Battered by strikes, rising costs and weak platinum prices,Lonmin said last month it planned to raise the money and another$370 million in bank loans to refinance debt due in May 2016.
The firm, founded in 1909 as the London and Rhodesian Miningand Land Company, said that if shareholders do not approve therights issue at a meeting on Nov. 19, lenders would not providethe loans to push back the maturity of the 2016 debt to 2020.
"As a result, the group may have to cease trading at somepoint between December 2015 and May 2016 and shareholders couldlose the entire value of their investment," the company said onits website.
Lonmin was hit harder than other producers by the platinummining strike in 2014, South Africa's longest and costliest, asunlike its peers, virtually all its operations are concentratedin the strike-affected Rustenburg area.
To try to turn around its fortunes, the miner announced aplan in July to close or mothball several mine shafts, puttingthousands of jobs at risk. It employs around 38,000 staff,including contractors.
SOME SUPPORT
The cash call has the backing of Lonmin's third-largestshareholder, the Public Investment Corporation (PIC), which hassaid it was willing to take up more than it is entitled to. TheSouth African government-owned PIC owns about 7 percent ofLonmin.
The company said the Bapo Community, which owns 2.24 percentof its shares, would also back the rights issue.
Other top four shareholders in the company include SouthAfrica's Kagiso Asset Management, Capital World Investors andOld Mutual Investment Group.
Lonmin said the new shares would be issued at a "significantdiscount", underscoring a more than 80 percent tumble in itsstock price over the past year.
"We see this as a particularly stark warning by Lonmin butit is a reminder of the extreme pressures faced in the SouthAfrican platinum industry," Investec said in a note.
Spot platinum has fallen by about 20 percent over thelast year to levels last seen in 2009 due to oversupply concernsand slowing demand in top consumer China. (Reporting by Zandi Shabalala; Editing by Tiisetso Motsoenengand Louise Heavens)