Ross Webster (Robert Vaughn): Colombia has two important exports and one of them's coffee.

Shortly after Superman disrupts Ross Webster’s scheme to destroy Colombia’s coffee industry by getting Gus Gorman to reprogram the Vulcan Weather Satellite to alter the weather, he cooks up a plan to kill Superman. He explains in a voiceover:

How did Gus know that Superman was from the Xeno Galaxy? Anyway, the Vulcan satellite performs relatively well and outputs the following:

There it is! The formula for making Synthetic Kryptonite... well almost. Apparently, a small percentage is made up of an unknown component. Of the known components, plutonium, tantalum, xenon, promethium and mercury are real elements. Dialium is type of bean, not an element. Xenon, the primary component in Synthetic Kryptonite, is actually a noble gas. It is chemically inert; it will not fuse with other elements under intense heat. Also, the constituent elements of a compound is rarely enough to produce it. For example, if the Vulcan satellite scanned a human being, it might output:

HUMAN BODY

COMPONENTS
==========

OXYGEN.....65.00%
CARBON.....18.00%
HYDROGEN...10.00%
NITROGEN....3.00%
CALCIUM.....1.50%
PHOSPHORUS..1.00%
POTASSIUM...0.35%
SULFUR......0.25%
SODIUM......0.15%
MAGNESIUM...0.05%

Those elements are readily available and extremely cheap. Though, putting them together to form a human being is a tad difficult.

Interestingly, Superman Returns (2006) reveals kryptonite as, “Sodium lithium boron silicate hydroxide with fluorine.” A recently discovered mineral called, “Jadarite,” has a similar composition. Sadly, jadarite hardly resembles or behaves like the green, fictional kryptonite. But, it doesn’t matter anyway. I like Gus’ formula better.

Gus needs a substitute for the unknown component and he finds inspiration on a carton of cigarettes.

This is a splendid example of product placement. Not only could you smoke indoors back then, you could put cigarette advertisements in children’s movies. And mind you, this is four years before the introduction of Joe Camel. But, this is nothing compared to Superman II (1980) (Adobe Flash Player required):

Cigarette tar in mind, Gus alters the formula:

He prints it out for the “the boys at the lab”:

I love that warning at the bottom:

WARNING :- WHEN THE ELEMENTS COMBINE AN INTENSE HEAT FUSION OCCURS.

THE COMPOUND FORMED IS KNOWN AS :-   K R Y P T O N I T E.

Apparently, “the boys at the lab” just ignore the warning. Anyway, Gus picks up the Synthetic Kryptonite after a brief nap:

Gus: What the hell am I afraid for? I'm from Earth.

15% of the formula is plutonium! I’d be afraid of that. Radioactivity exposure is not a good thing. In fact, promethium is radioactive as well, though much less so. Like radium, promethium was used in luminous paint for watches. I wouldn’t wear a faintly radioactive watch let alone go near this crystal.

Gus presents the Synthetic Kryptonite to Superman in front of a large crowd:

You’d think that Superman would think twice about accepting a chunk of green glowing crystal by now. But, he accepts it and instead of killing him, it ultimately turns him evil.

What exactly was Gus’ plan here? In the original Superman (1978), we learn that several minutes of kryptonite exposure are required to kill Superman and he senses pain and anxiety during exposure. In fact, later in the movie, Gus’ Ultimate Computer blasts Superman with intense kryptonite rays for a few minutes. It weakens him, but it's not enough to kill him. If Superman had accepted a chunk of real kryptonite from Gus and failed to visually recognize it, you’d think that he would quickly detect that he was getting exposed and toss the crystal away. Then, he’d confront Gus. I guess Gus thought that the moment that Superman touched the crystal, he would immediately keel over. Suppose Superman did. Wouldn’t the crowd of people confront Gus? In either case, this was not a good plan.