What is the relationship between Aurizon and coal in the context of the input sentence. Choose an answer from: product/material produced; manufacturer; distributed by; industry; position held; original broadcaster; owned by; founded by; distribution format; headquarters location; stock exchange; currency; parent organization; chief executive officer; director/manager; owner of; operator; member of; employer; chairperson; platform; subsidiary; legal form; publisher; developer; brand; business division; location of formation; creator.

Prescott quietly slipped out of Aurizon last week, and the public formalities of Monday's obviously solid annual results announcement provided a timely platform for chief executive Lance Hockridge to reassert a recovery of focus on his core coal business and on sating senior owners' expectations that he is running an annuity investment.
product_or_material_produced