MAC Green Room is a slightly cool-toned, medium-dark teal with a satin finish. It is a limited edition eyeshadow that retails for $17.00 and contains 0.05 oz.
MAC Green Room Eyeshadow ($15.00 for 0.05 oz.) is described as a "mid-tone teal [with a Satin finish]." It's a cool-toned, medium-dark green-teal with a mostly matte finish. There's a very, very subtle sheen to it, but applied, it really looks and acts like a matte finish eyeshadow. Giorgio Armani Iridescent Jade (LE) is more shimmery. NARS Misfit #2 (P, $24.00) is brighter. MAC Newly Minted (DC, $15.00) is warmer. Obsessive Compulsive Cosmetics Turquoise (P, $14.00) is brighter, lighter. Make Up For Ever #53 (P, $20.00) is greener. See comparison swatches / view dupes.
FURTHER READING: Formula Overview, which is a detailed review of the range as a whole.
M·A·C Eyeshadow is a highly pigmented powder formula that applies evenly and blends well. Suitable for use either wet or dry, it's available in a wide variety of textures and finishes.