My next door neighbor just gave me 2 lapidary saws which are 16" steel disks about 16 guage thick which use grit and water to cut stone.  Does anyone have any idea what kind of steel these are made from?  I haven't had a chance to spark test them yet.  I suspect they are something better than mild steel.

Thanks.

GNM

Rock saws have edges of diamond grit in a metal matrix and are very thin. In use the blades have to remain straight to avoid damaging the stone or ruining the slab with a curved cut. IN use they're under virtually no stress they just hold the diamond in gentle contact with the stone so work hardening isn't likely ever. Lastly I don't recall any of Dad's saw blades rusting even sitting in a damp environment in a saw for months unused. 

Lapidary rock saws are what I'm talking about, not sidewalk or other rough duty diamond saws. But that's what I recall about lapidary diamond saws, Thin, stiff, and don't rust or Dad's didn't. 16" sounds right for his "regular" saws his big saw blade must've been around 30" and didn't get used as often. I'd be making a WAG at alloy though. 

Thanks for the question George, now I'm visualizing and hearing Dad's rock saws. Good memories.

Frosty the Lucky.

 

4130 or 4140 are good guesses for sawblades with cemented teeth or abrasive grit.