Malga Mine is where Rolent gets most of its sepith from, esmelas in particular, to use as export goods.
In S.1202, a large piece of septium ore was discovered. After Estelle and Joshua finish their mission at Perzel Farm, they are quickly assigned to fetch this Septium Crystal for the mayor. When they reach the mine, Miner Landan was keeping lookout for monsters and he let them into the mine. When they found out that the elevator to the bottom level was locked by a key, another miner on the top level gave them the key. They soon talked to Mine Chief Gaton who gave them the esmelas septium crystal for the mayor, but a monster infestation soon broke through to the whole bottom level of the mine. The bracers soon went through the whole bottom level to rescue everyone. When their job was over, only one miner ran away from it all as he was the one who started the whole mess. Estelle still had the septium crystal safe and sound and both bracers left for the Mayor's Residence. It is later revealed that Kyle Capua was responsible for the cave-in.
Later on, the Septium Crystal was stolen, but it was retrieved. It was then refined and decorated, and gifted to Queen Alicia von Auslese for her birthday as a present from the people of Rolent. Mine Chief Gaton later reveals to Estelle that the hole has since been blocked up.
The orbal shutdown makes the mine a dangerous place, and some miners become stranded, requiring rescue. Estelle and Joshua, along with their party managed to rescue them and resolve the situation.