A red Geodude isn't in any of the Pokemon games, unless it was imported into a ROM hack.
A gold geodude is just a shiny geodude you must keep finding geodude in granite cave until its shiny.
Geodude and Onyx
You can find a Geodude in just about any cave or certain patches of grass. Also breaking rocks using rock smash has a chance of encountering a Geodude.
Anywhere you can find geodudes, but they are extremily rare.
Granite cave.
you can find geodude in most places. they are common by oreburgh city, and a ruin maniac has two in the ruins. people also have them near eterna forest. this answer is by GMAN123 :)
No, Geodude is not known to be found in the water areas in Pokemon Diamond, Pearl, and Platinum, unless it was cheated with a cheating device.
Search any cave you can until you find one!
You can find one in granite cave.
when you get the quest stay in the building got to the guy in red in the back straight ahed he will ask you if you want to go in the safari zone for 500 money say yes and go in and look for a geodude i did that the first one i saw was a geodude
What you have encountered is a shiny Geodude, which, as you described, is gold and a normal Geodude is a light gray color. Think of shiny Geodude as a gold nugget and a normal Geodude has a regular rock.
Geodude will evolve into Graveler.