This was my first attempt at making a somewhat natural shad color, it's not perfect but I was pleased with the results and thought I'd share them and the recipe as it was easy to make yet looks good (IMO).
Top color
1 cup of plastic
1/8 tsp silver pearl
1/8 tsp silk pearl
1/4 tsp holo flake
1/8 tsp .008 black and .008 silver
Bottom color
1 cup plastic
1/4 tsp pearl powder
1/4 tsp holo flake and .008 silver
A little bit of .008 gold and .008 black (around 1/32-1/16 of a tsp)
Side note if you want to darken up the back 3-5 drops of do it black works well and has a cool effect with the silver pearl, I didn't do it with these baits but have on a similar back color