I found a diamond on the 13th floor of the mine, does this even happen?

[Wice]

I was just exploring the mine and extracting stone, as I found a gem deposit on the 13th floor
when i broke it i got a diamond
I read on stardew valley wiki that the diamond can be found from the 50th floor
here is the link Stardew Valley 2022 11 12 10 08 24 02 DVR - YouTube (1:59)

P.S. Sorry if there are errors in the text, I am Russian-speaking and translated using google translator

 

[FilthyGorilla]

You probably found a regular gem node which can also drop diamonds or killed a monster (if you have reached the bottom of the mines) and thought it was a stone.

 

[One More Day]

Diamond nodes only appear below floor 50

Gem nodes can appear anywhere and still have a chance to drop a diamond