Save gradient presets
As with shape styles, after you create a gradient, you can save it in the Library.
Save a gradient in the Library
Select the object with the gradient to save.
From the Gradient preset pop-up menu, choose Save Gradient.
In the Save Preset To Library dialog, enter the name of the gradient.
The custom gradient appears in the Gradients category in the Library. Custom presets can be identified in the Library by the small user badge that appears in the lower-right corner of the larger gradient icon. The gradient also appears in the Gradient preset pop-up menu.