There is much to consider when purchasing a diamond especially diamond engagement rings! The tradition of presenting a woman with a diamond engagement ring when proposing began in 1477 when Archduke Maximilian presented a diamond ring to Mary of Burgundy and in most cases, the woman you plan to propose to will expect a ring to accompany that proposal!
First, determine how much ring you can afford. Most people use the two months salary rule. This means that the ring should cost the equivalent of two months of your current salary. Because you have other bills to pay, saving up this amount of money may take quite a bit of time. You should consider financing. Simply go to the jeweler of your choice and tell them that you plan to buy an engagement ring, and that financing will be necessary. Go ahead and get the credit check out of the way, find out what your payments will be, and how much of a down payment is required.
Now, have your mother, sister, or your girlfriends best friend take your girlfriend shopping, and make sure that they gaze at the engagement rings to get an idea of what she might like. Make sure that the jewelry store you buy the ring from will allow...