A diamond with ruby engagement rings can look absolutely splendid, especially when it is served up with a platinum ring. The white shine of the platinum really sets off diamonds and rubies wonderfully.
It is a good idea to browse the many online stores and local jewelry stores to see what they have. There is a very large variety and you want to be sure you are getting good value for money. There is plenty of information on this site about diamonds and how to select them. You can also go to All About Rubies and find out how to select the best rubies as well.
Make sure the jeweler or dealer explains to you exactly what the diamond with ruby engagement rings he has includes. What sort of ruby is it? The color, size and quality is important. The same with the diamonds. What is the cut? The Color and clarity. Also what is the weight of the diamond(s). get this in writing so that, if you decide to get an independent appraisal (recommended), you can return the product if it does not match up to the appraisal.
It is a good idea to pay by credit card also so you have a record of the transaction in any possible dispute over payment or the quality of the product when received.
Therefore you should pick a dealer whom you can easily contact. Is there a fixed address and contactable phone number? That would be the sort of thing I would be looking for.
Buying from an auction is more tricky as it is difficult to return the goods if found deficient or not as advertised.
Until one is experienced it is better to not buy quality jewelry from an auction.
To ensure you get good quality diamond with ruby engagement rings you do need a bit of patience and do some homework or due diligence, but when you do, you can be handsomely rewarded!