The background to the dip high/top grade coking coal prices...

The background to the dip high/top grade coking coal prices (what the indexes cover) is a slump in steel prices. Something big is happening in China, which is pushing this trend.
Chinese steel, especially rebar, has typically been of abysmal quality. Chinese rebar for example typically breaks like a pretzel, or close to that. Easy to bend with bare hands. The Chinese regime has finally blown the whistle and is enforcing higher quality standards from September forward. It will be illegal to sell the rubbish they have made up to now. The result of course is that Chinese steelmakers are rushing to unload all current (el-cheapo) stock for whatever they can get, before the door closes in a few weeks. This rush to market has of course had quite a negative effect on prices. The demand for new production is therefore diminished till this lot has been used up in the Chinese Jerry building construction industry. Cash strapped Chinese steelmakers are much increasing the mix of lower grades of coking coal for now, if indeed they have not gone broke. One or two very big producers have gone bankrupt.
The surge will be absorbed and then there will be a rush to renew stocks with the higher grades which are the only grades allowed to be sold from September. They might not be that great, but just not as bad. You can work out the implications as well as I can, most likely.