Wolfram Technology Guide: Real-Time 3D Graphics  previous | next 
Full Support for Opacity
Mathematica fully supports opacity in all 2D and 3D graphics.
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Click for copyable input
Graphics3D[

 Table[{Hue[RandomReal[]], Opacity[RandomReal[]], 

   Specularity[White, 20], Sphere[RandomReal[6, 3]]}, {50}]]
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