Wednesday, October 25, 2017

Crave-worthy Cabs of the Season!


Every season has its colors and shapes. Winter is celebrated in white--even in the places where it never snows. Spring brings pastels along with tulips and daffodils. The color of summer is green; green grass, green leaves, and not to ignore the obvious, zuchinni!

THE GREAT PUMPKIN!

Fall, however, brings a riot of color and some great shapes for lapidary!  I don't consider myself a good stone carver, but using lapidary saws and grinders, I've managed to make a few fun cabochons to salute the season.

This pumpkin cab is about three inches across. When I first saw the slab, I fell in love with the colors that look like textures. It was only about five-eighths of an inch thick, so obviously, I couldn't go for a true rounded top. I did a slow slope up from the edges so there's no noticeable demarcation where the slope stops and the flat area begins.


HURRICANE SEASON!

Unfortunately, fall is also hurricane season. This one has been unprecedented in its scope and damage.

To me, this cab shows the the vision and emotion of being caught in the fury of one of those storms. The gray rain and objects being thrown through the air tell the story of the incomprehensible damage these storms can create.








FALL LEAVES!

These colors could absolutely have made a spring garden, but the reds and golds captured my heart as does the last flash of color as the leaves in the trees turn brilliant colors before they die and fall.

Crafting this cab was a bit tricky. The first thing I did was find a picture of a leaf, copy it, and print it out on heavy paper in a variety of sizes. I cut several out to use as stencils and ended up choosing one that was just over three inches tall.That meant I would have to do a smooth polished top, similar to the pumpkin, but because of the detail work, I couldn't make the slope as gentle.

I actually surprised myself and was able to do this entirely with my trim saw and grinder.  I used the trim saw the make the notches, and polished the notches VERY carefully with the edges of my grinder wheels.

PINE CONE!


Finally, here's a small pine cone I made of petrified wood (it seemed appropriate 😉) the uneven but almost parallel lines looked a lot like a pine cone once I scribed the shape from a stencil. The cabochon is sitting on some redwood from my back yard, and it's pretty close in size to the cones the trees drop.

The cab is slightly browner in person, but it went red every time I tried to take its picture. Do beautiful cabs blush???






INVITATION

If you're in the San Francisco Bay Area or will be the weekend of Nov. 4-5, (10 am to 5 pm) don't miss the Contra Costa Mineral & Gem Society Show. It's a fantastic show and we also have great education and fun for the kids.It will be at  Centre Concord, 5298 Clayton Rd, Concord, (Clayton Fair Shopping Center, about 0.2 miles northwest on Clayton from Ygnacio Valley Road) Cross street
Balhan Drive, next to Clayton Valley Bowl, free parking. Scouts and military in uniform are free! Adults are $6, but you can download or print the coupon for $1 off at https://ccmgsshowcoupon.com/

Until next time,

Your Lapidary Whisperer,

Donna

Wednesday, October 11, 2017

DO YOUR CABOCHON STONES CONTAIN METAL?

You know how you sometimes see a stone or cabochon and say it has metal in it?  Maybe yes . . . maybe not exactly.

Here's the skinny on how to tell the difference. 

METAL- (Naturally occurring) consists of a single atomic element, like iron, copper, etc.
MINERAL - a combination of several elements and is generally crystalline, some of which can be processed into metal.

Right now, you're thinking to yourself, "Of course, I always go to to the atomic level of identifying the inclusions in my rocks." Relax. If you identify a streak of hematite as iron, you're right for your lapidary purposes. We're not evaluating the metal/mineral content to ascertain whether it can be profitably mined, we're helping those who love our work understand what they're seeing.

COPPER -  A Metal

For example, check out this nifty copper cabochon with an epidote matrix (according to the vendor I purchased it from) has the copper peeking through it.
 I've heard that this kind of specimens can sometimes have quartz in it, which would have lightened its look a bit, but all in all, I like the blue-green

TIGER IRON - Mineral

However, this Tiger Iron cab? Not exactly. 




The first time I saw a slab of Tiger Iron, I thought it was a very poor quality of Tiger Eye. But I was wrong.

Tiger Iron is a separate kind of mineral that combines Tiger Eye and Hematite in random patterns. Hematite itself, is a form of Iron Oxide which is where the "Iron" in Tiger Iron comes from. Depending on the amount of Hematite vs Tiger Eye, it can be very attractive. However, I prefer a lot more Tiger Eye than Hematite, so this isn't a favorite among my cabochons. The dark overwhelms the chatoyance. I see this from time to time at rock shows, but if I'm doing the buying, I'll get straight Tiger Eye any day.


PYRITE  - Mineral

I admit I love this cab!  It's quartz with pyrite  embedded in it. Because of the orange in the quartz and the shapes of the markings, it looks a lot to me like a magical fire. I wasn't able to catch the flash from the pyrite in a picture, but it's very impressive in person.

The Pyrite is a mineral (Iron Sulfide) and it's also known as "Fool's Gold". In some settings, like this, it actually looks more like the Iron it contains than gold, but if you've seen pyrite crystals, you understand where the name originated.






RUTILE - A Mineral

 When I first started admiring Rutilated Quartz, I thought that the different colors of the thin lines meant that they were different materials. Not so. According to Mindat.org, Rutile (TiO2) comes in Blood red, brownish yellow, brown-red, yellow, greyish-black, black, brown, bluish or violet.

Oxides are actually found in many stones. In rutilated quartz, the rutiles  can be made of tin oxide.   That's the same stuff in the white paste lifeguards at the beach smear on their noses to prevent sunburn. More importantly, in its dry form, it makes a wonderful lapidary polish.




Do you have any inclusions that you want to identify as either metal or mineral? Send me the information and a picture and I'll see what I can do to help you identify it.

In case you missed it, the cabochon from the last blog post was identified by  Burton Rondo as Bacon Opal with Hyalite, so he won!  A cab of the material is on its way to him!

Until next time,

Your Lapidary Whisperer,

Donna