Shield spikes are consumables in LotRO. They last 40 seconds. Useable by Guardians only, but the recipe is for Weaponcrafters. (Most Guardians take the Armorer profession instead of Weaponcrafter.)
Assuming you get the ore free from mining, the other ingredients (coal to make steel, and two spike molds) will cost you about 18 silver total. For that, you'll get 5 small shield spikes. That's almost 4 silver per spike to get a very short-lived, not-very-powerful buff.