⚙️ Anthracite Preparation: Dense-Medium Separation (2D)

This 2D companion strips the 3D coal-prep plant down to the physics that actually determines product quality: a heavy-medium cyclone sorting raw anthracite from waste rock by density, expressed as a real Tromp partition curve rather than a fixed threshold. Every particle gets a density sampled from the chosen seam's distribution and an ash content that follows the standard mineral-processing ash-with-density relationship; whether it reports to the clean-coal or refuse stream is then a probability set by how far its density sits from the medium's specific-gravity cutoff, with cyclone fouling widening that probability band over time until you flush it. The result is a live clean-coal tonnage, product ash and recovery readout that behaves the way a real dense-medium separation plant's does — trade-offs and all.