The Moho Mine is a level 3 structure available to both CORE and ARM. It is basically an upgraded Metal Extractor, and when built atop metal deposits it yields a production rate that ranges from +2.5 to +6.6; its maximum output is +19.2, however it can only reach this number in the Core Prime world. It also consumes only -15 energy when operational, however it takes much longer to build than its level 1 variant.
Because Moho Mines (5x5) are larger than metal deposits (3x3), it is possible to build them in nine different positions on top of a deposit without being penalized in the extraction rate, thus it is still possible to build a Moho Mine that will extract at its full rate even if there is a building right next to the deposit or if the terrain does not allow a perfectly centered construction. Moho Mines account for any metal that is within its 5x5 groundplate, so in a scenario where one is built fully covering one deposit and partially covering one or more adjacent deposits (usually only possible on a select few Tremblor maps), it will use the full extraction value of the deposit it fully covers and the partial extraction values of any covered adjacent deposits; this is also why a Moho Mine has such a large extraction rate on Core Prime maps, as it accounts for high static metal yield of each 1x1 map square being present in its entire groundplate.