Left to right, I've inspected the plastic switch pics and the Kailh based colors Kaihua named them. That's it, Kaihua. Your color naming scheme shan't confound these old eyes any longer!
What you call "silver", I call light gray. How you possibly got "copper" outta' the second pic... I dun wanna know. I no see copper, I see dark red. What you call "Gold", I call light orange, also "pizza puke orange" is acceptable. And the 4th pic, called "thick gold"? That's light brown. Maybe thick, generic, baby-poo brown. Certainly no variant of gold. Just my $.02
Everyone and their grandpa's obsess about 0.2mm of travel difference, colors and such for mechanical keyboards, for far too long. I dare TomsHardware to rise above all this LowNoiseAssChatter that has been going on since the invention of mechanical switches. Why not do some real technical reporting about pointing devices and their innards! Not just mice but also trackballs! Comprendo?