https://www.techradar.com/news/oneplus-6-glass-design-confirmed

The OnePlus 6 will have a glass design, as confirmed by CEO Pete Lau, marking the first time the firm has used glass on its flagship device.

Speaking in a forum post on the firm's website, Lau says the "OnePlus 6's glass design is centered around creating a 'sense of value' and 'premium hand-feel.'