Question: Siberian-Urals Aluminium Company comprises 19 businesses involved in the production of a chemical compound that naturally in what crystalline polymorphic phase?
Sentence (from "SUAL Group"): Siberian-Urals Aluminium Company (Russian: Сибирско-Уральская Алюминиевая Компания ), commonly known as SUAL (Russian: СУАЛ ), is a fully vertically integrated aluminium company that ranks amongst the world's top ten aluminium producers.
Relevant evidence: Yes