Medinah Minerals (MDMN)

[RD759]

That may be a function of the malleability and ductility of gold together with its relative softness (2.5 to 3). Native gold grains coming into contact may be attracted by surface electrical forces, and being rolled in the current may effectively 'snowball' and become compacted as they travel downstream (I have seen some pebbles coated in a sheath of gold on occasion, which suggests this sort of thing does occur). Platinum, on the other hand, is much harder at ~4.5 (Moh's scale is logarithmic) and though still ductile, it doesn't appear to behave in anything like the way gold does, often retaining good crystal form so long as the residence time hasn't been too long or the current too powerful.