Investors interested in stocks from the Retail - Jewelry sector have probably already heard of Signet (SIG) and Compagnie Financiere Richemont AG (CFRUY). But which of these two companies is the best option for those looking for undervalued stocks? Let's take a closer look.We have found that the best way to discover great value opportunities is to pair a strong Zacks Rank with a great grade in the Value category of our Style Scores system. The proven Zacks Rank puts an emphasis on earnings estimates and estimate revisions, while our Style Scores work to identify stocks with specific traits.Signet and Compagnie Financiere Richemont AG are both sporting a Zacks Rank of # 2 (Buy) right now. Investors should feel comfortable knowing that both of these stocks have an improving earnings outlook since the Zacks Rank favors companies that have witnessed positive analyst estimate revisions. But this is only part of the picture for value investors.Value investors are also interested in a number of tried-and-true valuation metrics that help show when a company is undervalued at its current share price levels.Our Value category grades stocks based on a number of key metrics, including the tried-and-true P/E ratio, the P/S ratio, earnings yield, and cash flow per share, as well as a variety of other fundamentals that value investors frequently use.SIG currently has a forward P/E ratio of 5.97, while CFRUY has a forward P/E of 19.88. We also note that SIG has a PEG ratio of 0.75. This figure is similar to the commonly-used P/E ratio, with the PEG ratio also factoring in a company's expected earnings growth rate. CFRUY currently has a PEG ratio of 1.05.Another notable valuation metric for SIG is its P/B ratio of 2.37. Investors use the P/B ratio to look at a stock's market value versus its book value, which is defined as total assets minus total liabilities. By comparison, CFRUY has a P/B of 5.87.These are just a few of the metrics contributing to SIG's Value grade of A and CFRUY's Value grade of C.Both SIG and CFRUY are impressive stocks with solid earnings outlooks, but based on these valuation figures, we feel that SIG is the superior value option right now. Zacks Names "Single Best Pick to Double" From thousands of stocks, 5 Zacks experts each have chosen their favorite to skyrocket +100% or more in months to come. From those 5, Director of Research Sheraz Mian hand-picks one to have the most explosive upside of all. It’s a little-known chemical company that’s up 65% over last year, yet still dirt cheap. With unrelenting demand, soaring 2022 earnings estimates, and $1.5 billion for repurchasing shares, retail investors could jump in at any time. This company could rival or surpass other recent Zacks’ Stocks Set to Double like Boston Beer Company which shot up +143.0% in little more than 9 months and NVIDIA which boomed +175.9% in one year.Free: See Our Top Stock And 4 Runners UpWant the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report Signet Jewelers Limited (SIG): Free Stock Analysis Report Compagnie Financiere Richemont AG (CFRUY): Free Stock Analysis ReportTo read this article on Zacks.com click here.Zacks Investment Research