Reflective panel

A substrate coated with a stack of layers comprising, in order, at least:

• i. a transparent substrate (S);
• ii. a first dielectric layer consisting essentially of TixZryOz (TZO), wherein x, y and z are each a number greater than 0, which is a high refractive index dielectric layer (H1) with a refractive index n at a wavelength of 550 nm between 2.1 and 2.8;
• iii. a second dielectric layer having an optical thickness of from 95 nm to 200 nm which is a low refractive index dielectric layer (L1) with a refractive index n at a wavelength of 550 nm between 1.4 and 1.8;
• iv. optionally, a third dielectric layer consisting essentially of TZO;
• and
• v. a single layer (C) consisting essentially of chromium,
• wherein a glass-side light reflectance is greater than 50% and a coating-side light reflectance is greater than 50%,
• wherein the first dielectric layer is in direct contact with the transparent substrate,
• wherein when the third dielectric layer (H2) is present, the optical thickness of the third dielectric layer (H2) is 95% or less of the optical thickness of the first dielectric layer, and
• wherein the coated substrate has a light transmission of at most 2%, and
• the coated substrate is thermally temperable such that after a heat treatment in a static furnace at 670° for four minutes the light transmission remains at most 2%.