We'd recommend a diamond carbide "burr" instead of a drill bit Swizz, like the ones shown/used on Denise's stone sculpture projects in that thread.
We use either a rounded ball tip or flat tipped cylinder shape to "drill" holes in a stone. The cylinder shape seems to be easier to keep straight to me though.
I'd say do a two or three stage/size drilling for the pin size hole needed. Make sure the dremel or drill used turn slowly otherwise you'll just toast off the diamond plated carbide then you'll just be rubbin' metal on the rock.
Keep it wet and go slowly, you'll get a feel for how fast to go and what is too fast real quick, especially if you check or keep a finger tip close to the hole being worked. You'll feel it get warm if you're trying to work it too quickly.

To minimize chipping, I use a depth gauge (toothpick) and just before poking through the other side you can use a light to pin point the place on the undrilled side to give it a "divot" of the same bit which seems to really help with that chip out on the break through.

Due to the fine tolerances between the pins and the Lapis I cannot use an encrusted bit. It'll have to be a precision bit with a smooth point and shaft to keep the holes perfect. I'll be using the drill press. The Lapis scales are a "gem composite" so it may not be as difficult as solid Lapis. It is Lapis Lazuli... but crushed and re-formed by an unknown process. It can be chipped as the scales came with some minor chipping on the corners. It can be shaped and sanded on my bench sander so far without too much trouble.
All that being said, hopefully it'll drill fine with a quality metal or tile bit from the hardware store?

I just did a test-drill on it with a regular drill bit. The entry hole is clean and perfect but the exit hole is chipped out. If I use masking tape on the backside will it eliminate the chipping?

The burrs finish holes are actually very smooth but you will need to mic the size to fit the pins for sure. Any drill bit you'll find suited for stone will unfortunately probably have the same "encrusted" diamond carbide but I don't think that will cause an issue once you've got a burr/bit of the appropriate size picked out.
The reason burr work better is surface area to work with vs bits......burrs just have more diamond area to grind the stone which is really what it is rather than a "drilling" process.

You are keeping that stuff wet while sanding right?

Don't think tape will work on the chipping problem, try the divot trick from the post above.

No. Not using lapidary equip and bench sander is not water friendly. Just taking it slow.
Quote from manufacturer:
" ... requires no special lapidary equipment to cut and shape. Will grind, drill, and polish with care, as all natural materials can break."

Dan, have a look at this! Artu Bits
I talked to my local hardware guy and he suggested trying it... said they were really talking it up at the Stock Show. I figured "what the hay". The bit was not cheap at about $6 but did the trick! I couldn't believe it.
Clean entry and exit wounds with this bit.

Guess as usual, I had to be difficult lol

So excited!

Oh ok Swizz, my bad. I'd assumed it was a solid piece of lapis lazuli but I'm with ya' now, it's a composite material not actually stone.
Huge difference then and sounds like your right on track with it. Should be more like glass to work with, much softer and not silica/quartz stone so dust must not be so hazardous. COOL!
Not a bad price on that bit either compared to similar, sounds like it did well on this project.

So far - so good. The dust is definitely unpleasant. The composite is mostly Lapis... the rest is resins. They combine to make a beautiful but surely toxic cocktail. Using a respirator for this.

I can't wait to see this!!!

Difficult? Nah.... every build has it's challenges and that's what I love about the hobby. I get to learn new stuff almost every time. I'm enjoying learning the nuances of this composite material.

Well then let me welcome you to the club that Crusty and I belong to where membership only requires breathing toxic dust containing minerals from Afghanistan. Unless of course their source material came from one of the other small deposits elsewhere in the world, in which case no membership for you.


Have we decided on a common color for the sheath/holster? I've got a quart of light brown oil dye on hand, if that's acceptable I can bring some up when I stop by next weekend.

No respirator needed today. It's 50 degrees in the shade and feels like 80 in the sun so able to move the op outdoors.
Making progress with that Lapis but definitely slow going. Should have them rough-shaped today. Might be the last pic until I finish.... as not to give too much away. Gotta keep a little suspense for Crunchy.
20150205_114711 by ghostcreekmine, on Flickr

I'll go with any color he decides upon.
Knife is charcoal colored steel with nickel-silver bolsters and deep blue Lapis scales. My vote would have to be black if I were making this for general sale based on that color scheme, BUT not sure how black would work with the pea shooter. Mike's call.
I know.... let's put Lapis scales on the pea shooter!