It means that the jewelry is 14 karat gold. The karat system is a weigh of evaluating gold jewelery. 14 karat is a medium grade quality, excellent for everyday wear because it is durable. Sometimes if jewelry is small, jewelry kind of squish the grade label together hence the "g14ks" marking.
g14ks in the jewelry world translates to Gold, 14 karats. Meaning, that the two items of jewelry you have with these particular markings are real gold, and they are 14karats, which is the standard for real gold.