It is simple. Just go to Pewter City (you'll need the HM move cut). Go all the way up to the upper right corner of the city around that area you'll find a small house next to the museum. Cut the tree that's blocking your way and enter the house. Inside you'll find a scientist standing next to a table. Talk to him and he'll give you the Amber.
The old amber is the fossil of aerodactel go to cinnibar island to ressurect him/her
This item only exists in firered and leafgreen.
The Pokemon Aerodactyl can be obtained from the Old Amber. You can find the Old Amber from the Underground. Take it to the Mining Museum in Oreburgh City to obtain Aerodactyl.
the old amber reveals aridactul
Aerodactyl
You have to go to Cannibar island and go into the factory with the old man in front of it go inside head to the last room give the scientist the fossil and he'll give you an arodactyl
Dome Fossil = Kabuto (Lv 40, evolves to Kabutops) Helix Fossil = Omanyte (Lv 40, evolves to Omastar) Old Amber = Aerodactyl
An old amber is the fossil if you like for aerodactyl.
Because it old
You can't find the Old Sea Chart in FireRed.
after you get cut go to pewter city and go in the back entrance of the museum and talk to the guy in the back. then take the old amber he gives you to the cinibar lab to get it revived
Well you collect it from the cinninbar laboratory and it should be an aerodactyl if you ask me that is one great Pokemon you should train it