Help with Wheat Chain

Hey everyone. So I need some help. All the wheat chains I've found at around 22 inches in length in solid 14k gold have been MUCH MUCH MUCH lighter than the 3mm wheat chain from Avianne. Any idea what is going on here? Most I've found have been around 20g and this one from Avianne claims to be 92.4 g?

I'm specifically looking at wheat chains because I have heard they are among the strongest especially for slightly heavier pendants. Would love everyone's thoughts on this.