Which metal you select is a matter of personal choice and budget. If your fiancé always wears yellow gold, then you would select 14kt or 18kt, whichever fits your budget. If she wears white gold, yellow gold, rose gold and platinum, then you would select your favorite, again based on budget.
When you are deciding on whether to purchase 14kt or 18kt gold, you should remember that the higher the number, the higher the actual gold content. In each instance the gold is mixed with other metals to make a strong setting. 18 kt gold is more expensive than 14 kt, but it is also softer. 14kt contains 58.5% pure gold and 18kt contains 75% pure gold.
At LabDiamondRings.com we save money and the environment by utilizing 14kt and 18kt gold settings. Each of these metals is generally hard and makes an excellent choice for everyday wear.
If you are considering white gold or platinum, you may want to look into the latest white metal offering of Palladium. This newer alloy retains its white (silver) color and shine, is hypoallergenic and is often more popularly priced than gold or platinum. Palladium resembles platinum in its chemical make-up. Prices of gold and platinum change daily according to market increases (or decreases). Palladium is more stable in its pricing.
Platinum is the finest metal for fine jewelry making and is, in fact, more rare than gold. Because it is rarer, it is more expensive. Like Palladium, it is hypoallergenic. It is also very pliable which gives it properties where it can be stretched and maneuvered into exquisite settings. The number of customers selecting platinum has grown over the past several years, possibly because of its rarity and increasing value.