What is the relationship between Elementis and LONDON 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.

LONDON (ShareCast) - (ShareCast News) - Chemicals group Elementis (LSE: ELM.L - news ) saw its first half pre-tax profit decline, as its oil and gas related and businesses reported a drop in sales.

Answer: headquarters_location