Hey,
Nice find.
This is my first post here. I found it by doing some searches for mining and ball mill supplies.
However, I also build historical replicas of cannons (although I mainly do 15th century through napoleonic). There's several things you can do yourself to help identify what these are. The first thing is to establish the age of the items. Based on location and your description of the building, I would have guessed an old mining shack with gun ports for warding off claimjumpers. Most likely late 1800's to early 1900's, but in an arid climate earlier stuff would certainly be around as well.
You'll have to sacrifice one of the balls....
Cut it in half and sand/polish the face. Etch for 10 minutes with ferric chloride (pc board etchant found at Radio Shack or similar store).
Your looking for silica banding and grain striations. This will help differentiate between cast and wrought iron. If they are wrought...hang onto them, you have something worth a LOT.
Most likely, you will not see any of the figuring. I can give you picks of what you're looking for if you want.
Next, heat one half up to a bright orange (acetylene torch or furnace is needed) and drop immediately into a bucket of some motor oil. Take a file and try to file one of the edges and note the hardness...ie, does the file bite or just skate across. If it bites into it, heat back to orange and drop into water and repeat the file test.
Now take the same piece, polish and etch again. Scan the surface on a scanner if you have access to one and post the pic or email it to me and I can help you identify the type of iron/steel. (different grades of cast iron get pretty distinctive grain patterns).
When you go back to the site, look for nails in the boards and pull a few. Are they round or square? Straight shanked or tapered?
The iron railing....take a section of this and polish a small part and etch with the chemical. True wrought iron with silica banding would indicate late 1800's or earlier. (BTW original wrought is worth quite a bit as well if kept in it's original functional piece!)
Did you find any other objects around? Piles of rubble? Sluice type wooden troughs? How about small 1-2" wide strips of iron? Cannon carriages had very distinct types of iron strapping. If you find any other small items be sure to keep those as well!
Most of those seem like odd sizes for Spanish cannons. The small ones are too small for typical Spanish cannons, but too large for cannister or grape shot. The large ones look close to a 12 or 16-lb cannon projectile. These were massive cannons. I doubt anything that large was ever located in that region. Civil War era mortars fired balls of that size, but those would have been hollow with a small fuse hole. I don't of any mortars being used during Spanish occupation. Have you measured them?
It would be odd that cannon balls would be left behind. In the Spanish occupation days, those would have been a fairly precious commodity. If someone took the time to take the cannons, they probably would have taken the balls also. What depth were they mostly at? Did it look like someone buried them all together, or wer they strewn out at all sorts of various depths?
Regardless of what they are, nice find! I'm by means no expert, just a devoted hobbiest!
Really cool forums you got here!
P.S. The funny thing is....I was looking for mill balls to use as ammo for my cannons!
