It is located on the first floor of the Monarch Room in the battle to free Jill Valentine from her controlling device, but only if Wesker is defeated in battle before the seven minute time limit is up for you to receive it.
There is a trick where one can obtain multiple Hearts of Africa during the Wesker and Jill fight. If you have the Infinite Rocket Launcher you should be able to take Wesker out easily. After the fight he will drop it in between the stairs. When you get to the Jill Valentine battle, collect the gem, then quit the game and overwrite your equipment and status. Then go to "Continue Game" at the main menu and it should take you right back to the start of the Wesker battle. Repeat this and get as many as you possibly want.
- ?, ed (2010). BIOHAZARD 5 kaitaisinsho Revised Edition. Famitsu.
- Davis, H. Leigh, ed (2011). Resident Evil Archives II. Translated by Elizabeth Ellis. Indianapolis: BradyGames. ISBN 0744013216.
- kaitaishinsho, p.446.