A small amount of surface active agent such as thiourea is added to the electrolyte to prevent dendrite formation in the copper electrodeposit. Formation of dendrites may lead to short-circuiting when the electrode gap is minimized to reduce the solution IR drop.

The stamp "ED 24 K" on the back of a necklace indicates that the necklace is made of electroplated gold. "ED" stands for electrodeposit, meaning the gold was applied using an electroplating process. "24 K" signifies that the gold used is 24 karats, which is the highest purity of gold commonly used in jewelry. This stamp ensures the quality and purity of the gold used in the necklace.