Asteroid rings come in four flavors: Metallic, Metal-rich, Rocky and Icy. Lots of new minerals were introduced with the engineers update, here’s what I found each belt type to contain and the galactic average price when I mined the stuff. This list will come in handy if you go for mining missions or are looking for something particular.
Metallic: painite - 40500Cr, platinum - 19279Cr, palladium - 13298Cr, gold - 9401Cr, osmium - 7591Cr, praseodynium - 7156Cr, samarium - 6330Cr, silver - 4775Cr, gallite - 1819Cr, bertrandite - 2374Cr, indite - 2088Cr
Metal-Rich: gold - 9401Cr, osmium - 7591Cr, praseodynium - 7156Cr, samarium - 6330Cr, silver - 4775Cr, lepidolite - 2374Cr,
indite - 2088Cr, gallite - 1819Cr, coltan - 1319Cr, uraninite - 836Cr, lepidolite - 544Cr
Rocky: samarium - 6330Cr, indite - 2088Cr, gallite - 1819Cr, coltan - 1319Cr, uraninite - 836Cr, cobalt - 647Cr, lepidolite - 544Cr,
rutile - 299Cr, bauxite - 120Cr
Icy: bromellite - 7062, lithium hydroxide - 5646Cr, methanol monohydrate crystals - 2282 Cr, methane clathrate - 629Cr,
liquid oxygen - 263Cr, water - 120Cr, hydrogen peroxide - 917Cr… And very rarely, low-temperature diamonds.