The booster for the ring slots. The Ornament distributes the points it has (which are determined by its upgrades) according to the ratio of stat distribution of the rings.
For example, if we have four rings equipped, that will give in sum 359 Strength, 340 Spirit, 200 Luck and 167 Valor the distribution ratios for each attribute is:
Total = 359 + 340 + 200 + 167 = 1066
RatioStrength = 359/Total ~ 0.3368 , RatioSpirit = 340/Total ~ 0.3189 , RatioLuck = 0.1876 , RatioValor = 0.1567
Assuming your Ritual Ornament gives you 680 points you will get:
StrengthBonus = Ratio*680 = 229, SpiritBonus = Ratio*680 = 217 , LuckBonus = 128 , ValorBonus = 107