Get value of particle shader for a point

I'm trying to get and display the value of the particle shader for a point in a mesh.

Backstory: I've imported an fbx mesh, and have coloured it through the additive particle shader. I have text values associated with different ranges of colour shown in my shader. I'd like my cursor to show the text associated with the colour value of the mesh from the shader. I'm very new to Unity, so I was hoping to find some help!
FYI: this will be used in a build for Microsoft HoloLens, and I have the Mixed Reality Toolbox for HoloLens.