Color is from different oils they use as a carrier. Look at the info below some oils are clear other are yellow or even brown and green

EO = Ethyl Oleate. EO is a solvent, which dissolves the powder but its use is to thin the solution’s viscosity.It’s a thin and expensive oil, created from ethanol, and used as a rubber softener, solvent, and typically used by us as a base for steroid solutions. It provides smooth and painless injections, and will suspend compounds at much higher concentrations than just oil. (It will make 100mg/ml Prop completely painless…) And because it’s a solvent, it allows you to use less Benzyl Benzoate in your blends, however BA is still used to maintain sterilit.

GSO = Grape Seed Oil.GSO is called the ‘carrier’.A much superior oil for injections, as opposed to cottonseed oil, but also has a shorter shelf life. It should be stored in a dark place, at room temp.

CSO=Cottonseed oil.It is very thick, and has trouble flowing through a small gauge needle. It’s just a byproduct of the food industry, so it is cheap and readily available.

Also some people use Wesson soybean oil,corn,peanut oil,sesame oil, soy oil, and safflower oil,MCT oil,olive oil,etc.

There are some other carrier oils available like rice oil, apricot kernel, coconut, sweet almond oil, avocado, flaxseed, and watermelon seed oil.

What oil is the thinnest?

Castor – 297.0 thickest
Crambe – 53.6
High oleic safflower – 41.2
Peanut – 39.6
Sunflower – 37.1
Grapeseed – 37.0
Sesame – 35.3
Corn – 34.9
Cottonseed – 33.5
Soybean – 32.6
Safflower – 31.3 thinnest

Pin a cc of each, in each calf for comparison..

I also heard that if you taste it and its spicy its gtg.

I bet there is a HUGE discussion page you can ask the same thing on and the source can answer it for you, would you look at that?