Monitoring wellbore fluids using metal ions from tracers

A wellbore tracer system comprising:

• a first tracer comprising a first layer of a first type of metal ions and a second layer of a second type of metal ions, wherein the first tracer is positionable at a first production zone of a wellbore and is configured to release at least one of the first type of metal ions from the first layer or the second type of metal ions from the second layer into produced wellbore fluid in the wellbore, wherein the first layer is positioned atop the second layer within the first tracer;
• a second tracer comprising the first type of metal ions, the second type of metal ions, or a third type of metal ions, wherein the second tracer is positionable at a second production zone of the wellbore that is different from the first production zone, wherein the second tracer is configured to release at least one of the first type of metal ions, the second type of metal ions, or the third type of metal ions into the produced wellbore fluid;
• and
• a detector positionable proximate to a surface of the wellbore and configured to analyze a sample of the produced wellbore fluid to identify the first production zone or the second production zone of the wellbore that is a source of the produced wellbore fluid based on determining which of the first type of metal ions, the second type of metal ions, or the third type of metal ions is present in the sample.