find prefabs that extend Base Class c#

hey i would like to know how to find all my prefabs that extend my base class

eg

im making a 2d game and have tones of tiles i load my level from an image where i find the pixel on the image and load the tile thats spawn colour is the same as the pixel

right now im defining the tile and there spawncolours in a script

for example public class objects { public Transform rockObject; public Color rockObjectColour;

     public Transform grassObject;
     public Color grassObjectColour;
     public int grassSpawnNumber = 1;
     public Vector3 grassRandomOfset = new Vector2(0,0);
 }
 public objects Objects;`

and to spawn my colours im using

if(objectColours[x+z*levelWidth] == Objects.rockObjectColour)//if the selected colour = the colour of the rock { currentObject = Instantiate(Objects.rockObject, new Vector3(x,0,z) , Quaternion.identity) as Transform;

}`

what i need to do is instead of having to define all my tiles and their colours in the script have a base class

 public abstract class Tile : MonoBehaviour {
 
     Public String TileName = rocktile;
         Public Color TileColour = red;
 }

and attach this it all my tiles i will have and make them all prefabs. so instead of having to define them i could just say something like: If (objectColours[x+z*levelWidth] == Tiles.red) then spawn rock

Thanks for Reading ~Scott