Here are the trainers who have Geodude as their Pokemon in Pokemon Diamond and Pearl: Camper Zackary, Hiker Daniel, Younger Austin, Hiker Kevin, Hiker Justin, Hiker Robert, Ninja Boy Fabian, Hiker Louis, Collector Dominique, Ruin Maniac Bryan, Skier Bradley, Youngster Darius, Youngster Jonathon, Leader Roark, Worker Colin, Hiker Reginald, Ruin Maniac Gerald, Ruin Maniac Karl, and Worker Quentin.
And in Pokemon Platinum: Hiker Daniel, Hiker Justin, Hiker Kevin, Hiker Louis, Youngster Jonathon, Youngster Darius, Leader Roark, Worker Colin, Worker Mason, Hiker Reginald, Ruin Maniac Gerald, Ruin Maniac Karl, and Worker Brendon.
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.
No, Geodude is not a real creature. Geodude is a fictional character only in the Pokemon franchise.
A gold geodude is just a shiny geodude you must keep finding geodude in granite cave until its shiny.
geodude evolves at lvl 25.
A female Geodude can be found randomly in the wild. A Geodude has a 50% chance of being female.
There are three Pokemon in the Geodude evolutionary line - Geodude, Graveler, and Golem. Geodude evolves to Graveler at level 25, and Graveler evolves to Goiem by being traded.
Geodude evolves into Graveler, starting at level 25.
geodude learns rockthrow at lv. 11
Geodude evolves at lv. 25.
Geodude has a mouth and apparently it can shoot flames.
put geodude as the party leader