Amalgam (dentistry) packs the plastic mass, before it sets, into the cavity. The amalgam expands ≈0.1% over 6–8 hours on setting. The final structure is a metal matrix composite, where γ, η and γ phases, are a matrix for unreacted original alloy, minus the fast-reacting β-phase and excess Sn. Amalgam is a mixture of two or more metals (alloy) with mercury which has been purified first by distillation to remove impurities. Currently, major components of the alloy are silver tin and copper. The composition of the alloy powder is controlled by ISO standard for dental amalgam alloy (ISO 1559) to control the
What They Always Tell Us What They Always Tell Us What They Always Tell Us is the first novel by Martin Wilson, focusing on the relationship between two high school age brothers as one begins to embrace his homosexuality. The book was a finalist in the Children's/Young Adult category at the 2009 Lambda Literary Awards, but lost to "Out of the Pocket" by Bill Konigsberg. "What They Always Tell Us" was also chosen for the ALA's 2009 Rainbow List. "What They Always Tell Us" is told from the perspective of two brothers, Alex and James. Alex is a high school junior who struggles with depression;