No, they said it was a diamond laminate. Which confirms that CIG's on-staff or consulting "physicists" that they were bragging about in 2014 weren't consulted or didn't graduate from high school.
If you know anything about diamond, creating large flat windows out of diamond is impractical, bordering on impossible: the largest naturally occurring diamond ever discovered measured 62.51x47.61x45.56mm. The largest artificially-created diamond crystal measured 25x25x25mm and was classified "vivid yellow-orange". So good luck seeing out of that window.
Furthermore, it's impossible to make diamond crystals curve, and adhesives don't like to adhere to its lattice, so you can't make laminates out of thinly-cut slices of diamond or composites out of powered diamond.
The only way to create the curved cockpit windows in Star Citizen is the same way we make canopies for the F-22 and similar aircraft--out of stretched or vacuum-formed acrylic. Which has a melting temperature of 320F vs. 1200C for fused silica, used in the triple-paned space shuttle windows. Even if you could, the reason why you don't make curved windows on something that has to survive the thermal stress of re-entry is because asymmetrical curved surfaces distribute the stresses of thermal expansion unevenly. In short, even if you solved the temperature problem (which would make manufacturing a curved canopy vastly harder), they would crack and fail under the heat of re-entry.
Also, diamond has absolutely terrible properties for use in windows that will be exposed to gunfire--diamond shatters when struck because diamond is exceedingly vulnerable to brittle fracture.
Finally, you'll never survive in space in a ship with diamond windows because diamond has high thermal conductivity and does next-to-nothing to shield you against high-energy cosmic particles. So you'll be alternately frozen and fried to a crisp, and then grow three heads and die from cancer.
