Prospecting Drill

Prospecting Drill

This mod was designed for no-ore-patch challenge runs. It adds a set of prospecting drills that spawn ores based on input. Drills consume ore-sample templates, detect the ore based on the chemical composition of the given sample and grow matching ore patches in a ring around themselves. There are three drill tiers, three sample tiers, quality-aware yield, and dynamic per-ore generation that picks up vanilla, Space Age, and modded ores automatically.

How it works

Find the Remnants, which are special rocks that stand out in the world. They will unlock the recipe for the 4 basic ores and provide samples for them. Research the base Prospecting tech to unlock the MK1 drill. Each ore has its own three-tier research chain (Prospecting: <ore> (T1/T2/T3)) that unlocks the matching sample recipes. Tier 2 also unlocks purification for that ore, and gates on tier 1; tier 3 gates on tier 2.

Craft a sample for the ore you want, then drop the sample into the input slot of a Prospecting Drill. Every cycle, the drill picks a random tile in its ring and either spawns a new ore patch there or adds to the existing one. Over time, the ring fills and the patches grow.

A regular mining drill that already ran dry on that spot starts back up on its own once ore regrows inside its mining area. It keeps its fuel, contents, modules and wiring; nothing is rebuilt or replaced.

The drill auto-selects its recipe from whatever sample you drop in, like a furnace. Mass-route any mix of sample ores and sample qualities to the drill: it processes whatever arrives. Please note that it's not a very good idea to just dump every sample you have in the same drill, unless you like sorting mixed ores.

Drill tiers

| Drill | Footprint | Ring | Cycle | Power | |---|---|---|---|---| | MK1 | 1x1 | 3x3 (8 tiles) | 30 s | 90 kW | | MK2 | 2x2 | 4x4 ring (12 tiles) | 20 s | 135 kW | | MK3 | 3x3 | 5x5 ring (16 tiles) | 15 s | 180 kW |

Sample tiers and yields

| Sample | Recipe (per 1 sample) | Yield per cycle | |---|---|---| | T1 | 2 ore | 3 ore | | T2 | 2 purified-ore, 2 steel-plate, 1 stone-brick, 1 copper-cable | 10 ore | | T3 | 1 purified-ore, 1 advanced-circuit, 1 plastic-bar, 5 sulfuric-acid | 50 ore |

Purification is its own step: 1 ore plus 10 water gives 1 purified-ore in a chemical plant.

Quality

Sample quality multiplies the per-cycle yield linearly: multiplier = 1 + 0.3 * quality_level. Normal is 1.0, uncommon 1.3, rare 1.6, epic 1.9, legendary 2.2. The drill always spawns normal-quality ore (engine limitation on resource entities), but the amount is bigger.

Quality propagates through the vanilla quality system, so a rare assembler making samples will produce rare samples, which feed back into the drill for bigger yields. If you have quality modules available and no mod to add drawbacks to them, they are very useful at increasing the yield of each ore. I tested this with a mod that adds more quality tiers and things worked fine (except the highest quality being slightly overpowered).

Bootstrap: remnants and the extract recipe

Rare worldgen structures called Prospecting Remnants spawn on configured surfaces. Mining one gives 1-2 random T1 samples for whatever is common on that surface, plus three rarer rolls: a 2% chance of a rare native sample (uranium, on Nauvis), a 1% chance of a sample from somewhere else entirely, and a 0.5% chance of a free MK1 drill.

Each sample-t1 also has a no-tech-required Extract <ore> from sample recipe that converts 1 sample back into 1 raw ore. That works in handcraft from the start. So a no-ore-patch challenge can bootstrap: find a remnant, mine it for samples, decompose a few samples into ore, smelt those to reach automation science, then research Prospecting normally and use the rest of your samples in a drill.

Settings

• Remnant spawn surfaces (comma-separated). Default: nauvis. Add other vanilla planet names or modded surface names as needed.
• Remnant spawn density per tile. Default ~0.0003 (about one per 3-4 chunks).
• Auto-generate samples for modded ores. On by default. Turn off for vanilla and Space Age only.

Compatibility

Made for Factorio 2.1 and Space Age. Version 1.0.7, for Factorio 2.0, was also tested with Exotic Space Industries: Remembrance. The mod scans every ore-bearing resource at load time, so heavy ore mods like Bob's Ores or Krastorio should pick up sample generation automatically (though Krastorio would likely not work at this point, since it's not compatible with Space Age). Modset-aware: if an overhaul mod oreswaps vanilla resources (e.g. Remembrance renaming iron-ore's mined output to ei-poor-iron-chunk), the loot tables and recipes follow the swap. If a mod adds a second resource that yields the same ore (e.g. Dredgeworks' submerged ores), the drill places whichever variant fits the ground it's standing on. Recyclable scrap is not treated as ore: Fulgora scrap, spaceship scrap and modded equivalents such as rubia's cupric and ferric scrap are inputs to recycling recipes rather than mined material, so they get no sample chain.

The hardcoded planet-to-ore mapping is vanilla and Space Age only; modded planets default to "no native ores" (remnants on those surfaces roll only the 1% off-planet bucket). The mapping can be edited in the mod's lua tables.

ESI:R 3x3 ore patches work, but are still the same size and you still need Deep Drills for them, they may not be the best unless you get them to a high ore count before starting to mine.

Known limitations

• Spawned ore in the ring is always normal quality, regardless of sample or drill quality. This is an engine constraint on resource entities, not a design choice.
• The MK3 drill accepts speed and efficiency modules. Productivity and quality are locked out: productivity by design (see Balance below), quality because spawned ore can never carry quality (engine constraint).