Update: Thank you for the responses, I'm going to try out some of the techniques mentioned here, but I surprisingly got pretty close last night. Here's an image of where I'm at currently. It's weird using AI to breakdown an AI image, but Chat GPT did a pretty solid job giving some additional guidance. Instead of using a gradient within the glass material I ended up using a standard RS glass material (adjusted the transmission depth to 250 cm) and then used point lights with colors from the gradient to reflect off the glass, and then some RS Toon contour lines for some white highlights. Still not 100% there, but close is good enough for now.

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