Any primitive collider placed onto an object in Unity need not be of a particular size or position. Both of these properties can be adjusted by dragging the boundary dot handles in the Scene view after selecting the Edit Collider button in the Collider component on the Inspector. In the case of the Sphere Collider, due to its shape, there are Radius settings that will allow us to adjust the collider to better fit the artifact piece. In the field for Radius, type in the proper value. Make it a bit larger than our artifact piece so that it will allow the player to pick up this object more easily.
Now, we will create a point light and choose a warm yellow color. Set the intensity to 2.0.
A point light for each piece will be heavy for the GPU if we cast the light on the whole world. We will optimize the performance by changing the culling settings so that the light affects only the artifact piece: pick the mask setting of the light and select Nothing, then select Collectible. You will see that only the piece is getting light from the source:
