What’s the difference between polarized sunglasses and gradient sunglasses?
Let’s describe each type of sunlens first:
Polarized lenses are typically solid and dark in color. An 
additional layer is added to the lens to block out glare from horizontal surfaces such as the hood of a car, the water, and the snow. We recommend adding an anti-reflection coating to the back surface to eliminate all reflections providing the most comfortable vision outdoors. The frame featured to the left is a Calvin Klein sunglass, it can be purchased with plano (no prescription) polarized lenses or with a prescription.
A gradient lens is darker on the top and lighter on the bottom. This design is 
ideal for reading outdoors, and/or leaving the sunglasses on for days that are not as bright. The density of the darkest part of the lens and the color can be varied to accommodate for each individual’s preference. The Gucci frame featured here can be made with a solid polarized lens also.
This year, a lens combining the attributes of the polarization and the gradient tint became available. The color of the lens and lens materials are limited, but we are very excited to expand your sunlens choices. 
The Lani by Maui Jim is an example.
Westside Optometry will be featuring all the Maui Jim Sunglasses at our Fall Eyewear Event, Saturday September 15th.
I purchased a pair of BeBe prescription sunglasses, the tint it dark gray. I asked for the gradient tint and was told I could not get the gradient tint with polarized added to the lens.
Here on your website I read that I can get the gradient tint with polarized glasses.
I’m sorry you weren’t able to get what you wanted. Gradient polarized are available. Xperio makes a gradient polarized in 6 colors.(grey mist and forest grey are 2 examples.) Sometimes there are limitations due to prescription strength and frame size.
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