Obsidian is an igneous rock that forms when molten rock material cools so rapidly that atoms are unable to arrange themselves into a crystalline structure. It is an amorphous material known as a  mineraloid .. The result is a volcanic glass with a smooth uniform texture that breaks with a conchoidal fracture (see photo on right). Obsidian is usually an extrusive rock-one that solidifies above Earth's surface. However, it can form in a variety of cooling environments: Black is the most common color of obsidian.
â¢ PEP TALK (noun). The noun PEP TALK has 1 sense: 1. a speech of exhortation attempting to instill enthusiasm and determination in a team or staff. Familiarity information: PEP TALK used as a noun is very rare.
The People Empowering People (PEP) program uses the definition of empowerment to connect research, theory, and practice. The Connecticut PEP program builds on theory of critical adult education developed by Friere (1970), Horton (1989), and others.