These came out OK. In retrospect, I should have made the original mold from some artificial shapes, not natural ones; it turns out the natural spears have a surface texture that is not really smooth.
Because the natural spears are uneven shaped (and large) making the mold resulted in a large block of silicone with multiple cuts in it to release the object. That means it has to be strapped together with strapping tape, then wrapped with plastic to prevent unauthorized resin excursions. It also turns out that for best results the mold’s first pour must be made with the mold at an angle so the bubbles can creep out, then a second pour on top of that, etc.
Yanking that much resin out of a block of silicone is good wake-up exercise.
When it’s plugged in it looks pretty neat:
I want to do another with a bit of UV sensitive pearl in the second pour, and be a bit more careful about pushing the light wires down into the tips of the spears.
The base of the spears is angled, so that the whole thing can be hung on a wall.
I have a silicone mold of a human brain, that I got when I was making soap. (I used Abbie Normal’s brain) and I think I’ll do a similar treatment. I need to make an interior form so that I can do a two-layer pour: pearl white on the outside and then a red interior.