Chalk produce, and thus widely used in the developing world, calcium-based chalk can be made where the crumbling particles are larger and thus produce less dust, and is marketed as "dustless chalk". Colored chalks, pastel chalks, and sidewalk chalk (shaped into larger sticks and often colored), used to draw on sidewalks, streets, and driveways, are primarily made of gypsum. Chalk is a source of quicklime by thermal decomposition, or slaked lime following quenching of quicklime with water. In southeast England, deneholes are a notable example of ancient chalk pits. Such bell pits may also mark the sites of ancient flint mines,
You-Are-Loved Chalk Message Project suicide prevention awareness campaign for LGBTQ college students. The project continued annually each October until 2012. In May 2012, the Chalk Message Project became part of Active Minds' National Day Without Stigma program. The Chalk Message Project raised awareness about suicide prevention for LGBTQ college students According to the Trevor Project, (a 24/7 crisis intervention and suicide prevention lifeline) LGBTQ youth are four to eight times more likely to attempt suicide than heterosexual youth. While little research has been done on suicide among LGBTQ college students specifically, a 2010 study from Campus Pride suggested a "chilly" climate for America's LGBTQ