It could certainly be from a tree or nursery stock.
A few years ago when working I found many tags from fruit trees and plants that had fallen to the ground and been buried for decades. I still have quite a few in different shapes and sizes. One unusual one is for Narcissus Masterpiece – this cast plant label measures 62mm x 18mm x 5mm thick, and so the mystery disk at 51mm across and 4mm thick is probably not an unusual size for a cast tag/label.
There was quite a bit of label production in the 1800s and 1900s. One report recommended writing the name on the tree trunk in case the label fell off in transit!
The attached advert from 1875 describes the newly adopted labels for the Royal Gardens at Windsor. The labels were made from ‘white metal’ with raised black-faced letters. They were made by J Smith, The Royal Label Factory, Stratford-on-Avon.
