>>31873383I'm not too familiar with geology, but you can probably expect decent mineral resources in the mountains, including lead, zinc, copper, and gold. Iron can also be found in decent quantity, perhaps more in the south as part of the Sakuran large igneous province.
As for rock types, southern Hoshiyomia will likely be predominantly ignerous due to the constructive plate boundary, so rocks like basalt and gabbro. In the north, the majority of rocks will be sedimentary in nature, although especially in the mountains, high-T, low-P metamorphic rocks like blueschist will be more common due to the stress caused by the orogeny.