At least three answers have said what I'm about to say. I upvoted all of them.
All of the periodic table elements needed to build a cell phone (Thanks @MS!) were well known and easily obtained 100 years ago. And yet the first cell phone wasn't invented 100 years ago. It was invented 50 years ago, and it was little better than a walkie-talkie. The cell phones of today could have been built (if all you care about is the list of elements) 100 years ago.
And yet they weren't.
I anticipate that 99.999% of the inventions in the next 150 years will be based on elements in the periodic table of elements that we know today. And yet if we were given one such invention to look at, we wouldn't be capable of building it any more than someone 100 years ago could a modern cell phone.
- We simply might not understand the physics behind it. I lived through what the following quote is talking about.
It has long been thought that building nanometer-sized transistors was impossible. Simply put, the physics and atomic structural imperfections couldn’t be overcome. However, scientists built fully functional, nanometer-sized transistors. They did so using atomically flat, two-dimensional molybdenum disulfide semiconductor and a single-walled carbon nanotube imbedded in zirconium dioxide.
Now, had we been handed such a creature, could we have figured it out? Probably. Significantly faster than the Real Life discovery? Probably not by much, because...
An entire infrastructure is necessary to manipulate raw materials in a way to make, for example, modern integrated circuits. Just because you can see what someone else did to make something happen doesn't mean you have the know-how to make it happen. There is a literal mountain of tools, technologies, factories, and experience holding up that glorious integrated circuit. The same would be true for your particle field.
Someone once said that "The phrase that typifies real discovery isn’t ‘Eureka’ but: ‘huh. That’s funny’.” If (and I stress, if) we can look at the atomic nature of the particle shield and see it's root assembly, it's highly unlikely our reaction will be "Eureka!" It's far more likely our reaction will be, "huh, that's funny." Elements of the periodic table have, as an example, ions. Ions can be positively charged or negatively charged. But the funny thing is, just because a molecule is made up of groups of ions, doesn't mean we have the slightest idea how all those ions were assembled. What chemical processes were required? What forces had to be brought to bear? How many proverbial goats had to be sacrificed?
In other words, insofar as we understand science today, of course the particle field is made up of elements we recognize. That doesn't mean at all that we have the slightest idea how to construct it.
After two thousand years we think we've figured out the secret behind Roman Concrete. Two thousand years! Modern analysis! Built from existing elements! And we actually knew how to make it in the first place! And yet it took two thousand years to figure out something that we'd forgotten.
It's completely believable that we'd have no idea how to make the particle field work. What doesn't make sense is that we'd be capable of creating an atomic duplicate and it not work. That requires something else that you're not telling us about. Like a soul or Dark Matter or some other quasi-mythical additive, because by definition, if no such creatures exist, then an atomic duplicate must work.
Or you can't make an atomic duplicate. Which is far more likely.
Huh... that's funny.