rellis 1962,
In my opinion, if your linotype has been lying around for 50 years and has no oxidation it most likely has had virtually alll the lead and tin boiled out of it in a type setters pot. Linotype had a heavy dose of antimony to begin with as it was needed for the type setting chore for which it was purchased. Most newspaper operations recycled their set type on a daily basis back into the melting pot above the type setting machine.
Can stilll hear the clackity-clack of a fast typer on a type setting machine.
Bet on it, you will need to add some lead and tin to your existing linotype. How much? Good guess for sure. The ole thumb nail scratching on the lead bar routine won't tell you much.
Let us know the lead/tin content of your treasure trove of linotype.