Since we may have a winner, please do not do anything else to it. You could easily lower the value of the item, should you decide to sell or donate it in the future. I know that many would be tempted to make it shiny, but just....don’t.
If you had brought the item to me, before the arthritis made it painful to manipulate rocks, I would have ground and polished an area of less than a half centimeter square. Once I got the window polished to 4000 grit or finer, an application and rinse of dilute nitric acid would have been checked for what is called Widmanstatten Pattern. While it is easy to find directions online to do this, it is far easier to find directions that will result in failure.
Back to your rock. While it has visual characteristics that could be interpreted as meteoritic in origin, it also has characteristics of a high grade iron ore nodule. Something not uncommon in parts of Arizona. One of the next tests will be that of nickel. Not an assay. Just a simple test to determine if nickel is present. Again, while examples of proper tests can be found online, examples of improper tests are easier to find.
Please ensure that a qualified professional gets ahold of this item. Way too many people with degrees in earth sciences have never attempted to identify a suspected meteorite. Any University or Museum that has a section that identifies meteorites should do.
Nearly every qualified professional in this field will require payment of some kind for their services. Monetary payment, a portion of the item being tested, or both. I used to charge between $10 and $25 just to open a small window.
My best to you on this find. Please keep the forum updated on each step you take.
Time for more coffee.
