The subscription price was 9p per share, with the shares to be admitted to trading on AIM on or around August 6, brining Al Marjan's holding up to 24.18%.
The large shareholder had previously sent a letter of intent to subscribe for the additional shares.
The proceeds will be combined with the recent placing for £11.5 million to support the next stage of development of the Mina do Barroso lithium project in northern Portugal and make a decision to mine.
Savannah will also use the cash for working purposes and to progress its projects in Mozambique and Oman, where it is currently applying for mining leases.
The company's shares were trading at 8.7p/share Wednesday morning, down 1.14%.