The bridal veil falls are volcanic sinter formation (silica).

Hot water overflows from the Champagne pool and eventually falls over this small cliff. The water is heavily charged with silica and other minerals (hydrothermal solution). The silica is deposited to make a "waterfall" of rock.

The sinter looks like the water it is deposited from. 

In this enlarged view, real water falls in the middle of the picture, then cascades down to the right.

New Zealand once had much better sinter formations, the Pink and White terraces, but they were destroyed in the Tarawera eruption.