Silvers:

Palladium/Silver alloy - AGPD - 58% silver, 25% palladium, 15% copper 2% zinc, making it much harder than sterling, but a little more affordable than white gold. It is darker than sterling, but a touch lighter than 14k palladium white gold. Color wise, it is cooler than 14kpw since it doesn't have the high yellow gold content to compete with. (due to drastically rising costs of palladium, the price has significantly increased)

Sterling Silver - 92.5% fine silver, 7.5% copper. This is a standard sterling alloy. Fine silver (99.9) by itself is much too soft (in my opinion) for a ring. Sterling is much softer in comparison to gold, which means it will wear faster, but the addition of copper makes sterling much stronger than fine silver. 

Palladium Sterling Silver - 92.5% fine silver, roughly 4.5% copper and 3% palladium. Palladium is a more precious metal and a relative of platinum. It gives a little added preciousness to sterling and makes it a little harder and a little more expensive. The color is nearly identical to regular sterling, but has a very very slightly warmer tone when they are next to each other and if you're trying to see a difference.

Argentium Sterling Silver - 92.5% fine silver, 7.5% copper and germanium. Though I don’t cast with it often, it is an option. Similar to the palladium sterling, some of the copper is replaced by another metal, germanium. It gives some different and unique properties to the alloy: different melting temps, tarnish resistant, fuses easily. I use this alloy for a lot of my wire work, ear wires, jump rings etc.

Golds:

All the gold I use are alloys. 24k is close to as pure as you can get with gold and it is very soft. Mixing it with different metals creates a variety of properties and colors.

Yellow Gold - a traditional yellow gold. All 14k alloys contain 58.5% yellow gold. The other metals vary per alloy and in amount. I buy all of my casting grain alloyed already, so the make up per % of the rest of the alloys is unknown to me. 

Palladium White Gold - 14k contains 58.5% gold, and instead of nickel as in traditional white gold, it contains palladium as a "bleaching" metal. The color is often referred to as “straw white” though I think of it as a “warm steel” color. It is a lovely soft and buttery gray color that is not plated in rhodium as traditional white golds are. If you are attempting to match a current white gold ring, be aware that it may not. It is the hardest of all the metals I use and is more expensive than other 14k alloys. The qualities that give it added hardness as far as wear is concerned, also make it harder to work with. This and the added value of the palladium are the reasons for it being more expensive than the other 14k alloys.

Palladium is in the platinum family and makes the alloy overall and more precious metal. (Though palladium is much less expensive than platinum!) If you want the bright white look, you are more than welcome to have your ring plated at your local jewelry store. Most rhodium plating needs to be redone every year or couple years depending on your wear. 

Palladium white gold will take a patina, though it is not as dark as the patina on sterling, nor is the contrast as great since the metal is darker and the patina not as dark. There are several comparison shots if you search for “comparison” on my flickr site: http://www.flickr.com/photos/bcyrjewelry The patina also does not wear as well and for most textures may wear off very quickly.

Rose/Red Gold - a lovely coppery rosy reddish toned gold - 14k contains 58.5% gold. Can take a light patina, though wears off more quickly, so starting out with just a little is best.

Other colors - Though not commonly used, brighter “royal” yellow, green and peach gold are just slight variations of a traditional yellow. Green gold is not actually green, but a greenish hue when compared to traditional yellow gold. 

18k alloys - contains 75.2% gold - due to the higher gold content, 18k alloys have a different color than their 14k relatives. Most commonly requested for the subtlety bands, though I can upgrade most styles to 18k instead of 14k. It is a little softer, though more durable, quite a bit heavier/denser, and as one might guess, more expensive.

Palladium and Platinum

I am not able to cast with either in my studio, though I use a larger casting company that has the facilities to cast both of these metals. The melting temperatures are much higher than I am able to do with the equipment I use for silvers and golds. A model can be made in sterling and then sent off to be molded and cast in either one. Generally this adds an extra 3 - 4 weeks. For some styles, such as the subtlety, love rocks, simple hammered or sands of time, I can buy a ring blank and create a ring that looks just like my cast bands. This is often less expensive and faster than having them molded and cast from a sterling model. 

The palladium alloy is Palladium 950 (TruPd from Hoover and Strong)

The platinum alloy is 95% Platinum, 5% Ruthenium.

Plating? None of my jewelry is plated in any metal. Rhodium plating is common for traditional white gold and much of the mass produced commercial jewelry is also plated in rhodium for a bright white finish that doesn’t tarnish. Plating WILL wear off over time. I do not offer the service, though most jewelry stores can rhodium plate a ring for you if you want. The patina finish that I offer will also mostly wear down over time. In the deeper textures, it may increase over time. Here is a comparison photo of the finishes on sterling. The finishes will look a little different on different metals. The patina is most durable on sterling.