The earring stud designs are made out of sterling silver and may be plated in 18K yellow or rose gold.  All stud earrings come with plated butterfly backs

On the other hand, the hanging earring designs are made our of either white metal, brass, or copper, but are still plated in either 18K yellow or rose gold.

All measurements are approximate:

• Small Cubes Studs measure 7.5mm tall x 7.5mm wide 
• Large Cubes Studs measure 14.5mm tall x 14.5mm wide
• Pyramid Studs measure 13.5mm tall x 13.5mm wide
• Diamond Lattice Studs measure 1/2" tall x 1/2" wide

• Small Hanging Cube Earrings are 13-16" tall x 9/16" wide x 13/16" deep and weigh 2.2 grams each
• Large Hanging Cube Earrings are 1-5/8" tall x 9/16" wide x 1-5/8" deep and weigh 3 grams each
• Hanging Fractal Cube Earrings are 3-3/8" tall by 1-3/8" wide and weigh 6 grams each

• Small Viper Hoops are approximately 1-3/4" tall by 1" wide, and weighs 5 grams
• Large Viper Hoops are approximately 3" tall by 1-5/8" wide, and weighs 12.5 grams