NARS Istria is a slightly cool-toned, very light pink with a pearl finish. It is a permanent lipgloss that retails for $26.00 and contains 0.18 oz.
Istria is described as a "pink glace." It's a light-medium, cool-toned pink with blue undertones and soft, white shimmer. It had semi-sheer color coverage that did not apply evenly, so it looked somewhat splotchy on the lips. It also settled into lip lines. The color wore well for three and a half hours on me. MAC Tender (P, $22.00) is lighter. Urban Decay Lovechild (P, $20.00) is less cool-toned. Urban Decay Obsessed (P, $19.00) is a touch lighter. NARS International Velvet (LE, $26.00) is lighter, less cool-toned. MAC Petite Indulgence (LE, $20.00) is darker. MAC Pagoda (LE, $20.00) is lighter. MAC Going Casual (LE, $20.00) is slightly darker. See comparison swatches / view dupes.
FURTHER READING: Formula Overview, which is a detailed review of the range as a whole.