Now I'm curious... if we were to include The Silmarillion, what would your new list look like?

Well, The Silmarillion complicates things unless you specify if the artifact ever existed or at a particular point in time. Many of the most powerful artifacts before the Third Age either didn't exist or were inaccessible after the First Age.

Okay, let me clarify. If you were to make a list of the top most powerful artifacts which have ever existed in Middle-earth, at any point in the timeline of Middle-earth, what would your top ten look like?

Hmm... top 10?

1. The Two Trees of Valinor

2. The Two Lamps of the Valar

3. The Silmarils

4. Grond, the Great Mace of Morgoth

5. The One Ring

6. Ringil, the sword of Fingolfin

7. Anglachel & Anguirel, the Swords of Eöl

8. Aeglos, Spear of Gil-Galad

9. The Three Rings

10. The Palantíri

I'm sorry it's this a personal list or a list put out by a big company because I have many things to say about this but I don't really want to offend anybody

Why does it matter if the list is a personal one or put out by a big company? Just evaluate the list based on what you think is accurate or not.

Nice, thanks for sharing! I hadn't thought about the Trees and the Lamps as artifacts, but it certainly makes sense.