Sculpting Spirit Stones

Hey there folks! There's been a few recent inquiries about how to sculpt Spirit Stones. Thing is, there's no "right" way, only whatever works best for you and the current piece. I know three different techniques to get the same effect and I'm sure there's more. (Feel free to share if you have a different method!) Please pardon the photos: I had to use Paint to edit as I recently upgraded to Windows 7 and can't find my Photoshop install disk...

Method 1: "Gem then Casing"
This is a two-step method. To start, you sculpt a protruding ovoid that becomes the gem. Let this dry. Then come back with a rolled out string of putty. Work it around the gem in a "C" shape to create the casing. Clean and smooth as you go until the ends meet. Remove any excess and then go back to clean up and shaping.
I find this method works best when you're sculpting the underlying layer and want to add a gem at the same time. It is mediocre for adding onto an existing layer as there isn't much surface area for the gem to stick to... even sculpting the casing can be enough pressure to break the bond.
Here's a straight shot...and an isometric.

Method 2: "Casing then Gem"
This is also a two-step method. Here you start with a flat circle of putty. Form your casing shape using a rounded tool, such at the top end of a small pin or a circular shaper. Press it into the center of the cicle and then rock the tool up and down to create your dished oval. Clean up as desired and allow this shape to cure. Then roll out a small ball for the gem and squish it in the center. Use a flat buffing tool to smooth the gem into place. If you squish too close to the casing, the blade point can be used to pick that back out.
This method is meant for applying to an existing surface, as it has maximized surface area. It is possible to do at the same time as an underlayer, but can be tricky as you have to press in and can easily mar the whole piece.
The two-step method does mean you have to wait to finish the piece. It is best for when you're creating several stones at the same time.
Here's a straight shot...and an isometric.

Method 3: "All at once!"
This is a single step method. Start with a protruding ovoid slightly larger than you would for Method 1. Then use the tip of a very sharp tool to press in around the edges to create the casing. Start at one side and work in both directions, so that you don't skew the shape when tooling. Once you've shaped the casing, go back to clean and smooth the piece. Be careful during this as it is easy to ruin the piece.
This method is only for applying to an existing surface. You CAN try doing this at the same time as the underlayer, but it will give you headaches.
The main advantage to this method is that it is done in one go. However, it is MUCH more difficult than the other 2 methods. It requires careful tooling and some sculpting experience to pull off.
Here's a straight shot...and an isometric.

Cheers and hope you enjoy!

As a personal note: No, I am not dead. :-p Life has been very busy both normally and at work. My 40k time has been cut drastically and my blogging time even more. I'm slowly getting back into the swing of things, but I expect the rest of the summer will still be slow. I hope to be more prolific after that!

***I'm sure the image is copyright someone, but I'm currently too lazy to hunt the name down... Used without permission, blah, blah, blah...***