Sand Spikes- Wagons West! (A Mineral Mystery)

Sand spikes are a type of concretion that formed in a very small area on the California/Mexican border.

I can't include pictures but I can give a graphic description. They range in size from about 1 inch to 3 feet. There is a "ball" or cluster of small balls on one end and a tail that tapers off.

Mineralogically, they are calcite based and are completely included with sand. The Barite Roses from Oklahoma do the same thing.

These spikes were first discovered lying loose on the ground from weathering. It wasn't long before people discovered they were in layers below the surface. One well-documented layer was at 3 feet deep and another was at 8 feet.

If that isn't enough to confound people, there is no evidence of fossils of any kind. No trace fossils, no seed fossils, they are just the sand and calcite.

But wait there's more! It wasn't long before everyone involved realized that they all had one other very unique characteristic. In uncovering the beds of them underground they all pointed directly west! The tail of 95% off the ones underground point west--as west as a compass.

Why were they pointing west? No one knows to this day. There have been many theories but so far none can be proven. Some are as funny as aliens. Others think they are some kind of growth that blew over in a windstorm.

When I was growing up every rock shop in the country had a basket of these curiosities. Several dealers went in and used heavy machinery to mine them. Unfortunately they were too soft and most were destroyed. Still many people have one in their collection.

We would love to see them if you have them. E-mail photos to rockshop@rocks4u.com, and we'll post them.

Rubies & Sapphires...

Most people are surprised to discover that rubies and sapphires are brother and sister. Both belong to the two child family corundum.

Corundum is a very simple mineral chemically, being only aluminum oxide. Corundum is second only to diamond in hardness. It has been the start of many a wars in history, and has created nature's most coveted and expensive gemstones.

Corundum is the family name and the two children are ruby and sapphire. Emery use to be a third child but it was the black sheep of the family and was cast out. It is non-gem grade opaque green. There was no sparkle to its history.

Rubies are always red. Not blueish red or purple, but RED. Any other color of corundum is called sapphire. Historically, sapphires were blue and other colors were discarded. Today other colors are called "fancy sapphires" and are almost as valuable as blue sapphires--with good cause since they are as beautiful!

There are many adjectives attached to rubies at the various jewelry stores in order to sell them. "Pigeon Blood", "Thai", "Rose", etc. are often used to describe rubies. The true standard of comparison are Burmese rubies. In the remote area of Mogok, Myanmar (formerly Burma) is the gemstone capital of the world--especially for rubies. Closed to outsiders, few westerners have ever been there. The BEST rubies in the world are mined there using century old techniques. Most people have never seen a magnificent ruby from there, as they are so rare and expensive--consistently bringing tens of thousands of dollars per carat. Some of the best bring in as much as $250,000 per carat. That makes gemstones a great source of portable wealth. It makes rubies the best deal also. Rubies are at least 50 times more rare than diamonds and yet only cost a few times as much. Besides that, gemstones almost always appreciate!

Gemstones in general and rubies in particular make the best gifts as they will never wilt, melt in your mouth, or depreciate. What more could a woman (or man) want?

Sapphires are more common than rubies and hence not as expensive. Most don't top over a few hundred dollars per carat and yet are very attractive stones in color and clarity.

There are many places around the world where sapphires are mined. These include: Mozambique, Madagascar, Brazil, Australia, Thailand, Vietnam, and Myanmar. In the U.S. they are found in gem quality in Montana and North Carolina. Non-gem grade material is found even more abundantly.

Rubies are red due to chromium. It is also responsible for making rubies fluorescent. Sapphires are colored by a ratio of iron and titanium. Every possible ratio produces a different color. Matched sets of sapphires are remarkable as the ratio must be exact to reproduce the same color again.

Pick up a copy of Fred Ward's book "Rubies and Sapphires" to learn more. He covers legends and lore, how they started wars, how to buy, how to care for them, and shows loads of pictures of famous stones.

Tumbled Stones Sampler

Crazy Lace Agate Basics

Zig-zag and lace are two words that best describe the pattern in crazy lace agate, which consists of many irregular curves and twists. The unusual pattern is caused by the agate forming on top of other crystals of aragonite or calcite. The layers of agate form a contour over the other crystals making this lace-like pattern. The sharper the crystals or more pointy the crystals of aragonite or calcite, the more the zig-zag the pattern appears.

Imagine if you strip down your bed to the mattress and put lots of tall kitchen utensils on the bed standing straight up and really close together. Now start placing thin blankets and sheets of red, white, gray, peach, and yellow, etc. on them. Once you have a foot of thin sheets and blankets draped over the utensils, you take a big saw and cut a cross section of the bed and blankets so you can see the inside. This is what Crazy Lace Agate looks like. And it is not much more comfortable to sleep on than the bed we just made.

The coloration of Crazy Lace Agate is usually a gray matrix with the bands being reds, browns, and yellows. If you are very lucky, you'll get greens and blues. In the 1920's to the 1970's it was common to dye this material all kinds of colors. Since the dyed material was sold in rock shops and tourist stops, question pieces you come across that are unusually colored.

Crazy Lace Agate has become harder and harder to come by. We don't currently have any in stock.

We have the greatest rock shop community!

Rockpick Legend Co. started as Lewis Rock Shop in 1964. Over the many years, a great "community" of customers has built the Rock Shop. We're never quite sure how to address our newsletters, since "Dear Customer" seems really cold, and not truly applicable to the relationship we feel exists. Most of our customers are friends and comrades. Here are a couple of unbelieveable, but true stories:

When we bought the Rock Shop in 1995 there was a rhodochrosite necklace in the store that Anita really wanted to keep, but we couldn't afford it. When Anita sold it, she mentioned how much she loved the necklace, too. A year later the "customer" that bought the necklace sent it to Anita with a note saying that they had enjoyed it for a year, and now she could enjoy it, too. We cried.

Our youngest child, Zeke was born in 1999. "Customers" brought us baby gifts. Our hearts were touched.

We've had "customers" give our children gifts based on the individual interests of the different children. "Customers" have brought us souveniers of their vacations--including some beautiful Mexican wall hangings. "Customers" have brought us lunch. We've received so many displays of kindness from our "customers," that we can't even mention them all here, even though we appreciate each and every one of them.

When we started this blog we sent an e-mail to our rock shop community asking them to help us compile copies of our 10 years of newsletters. Once again, we owe a great big thank you for the help we've received! I'd especially like to thank Sandra B. for sending in 11 articles.

Thank you all. Please comment on the articles if you've had experience with some rock, or been to some site. We'd really like to hear about it. If you'd like an article on a specific topic, please request it. E-mail me at rockshop@rocks4u.com.

Sincerely,
Rick Dalrymple

Blue Agate from Mexico

Blue Agate from Mexico is a very attractive blue with some tan matrix (most of it comes off in the tumbler). Most pieces are smaller than a silver dollar so it is already to go into the tumbler.

This material is very rare. It was mostly mined in the early to late 1980's and has been gone since then. When it was available, the wholesale price was around $25 per pound. We found an old time rockhound in Colorado who had a stash of it, and we were able to negotiate for his entire collection.

To see a picture of it before and after polished you can follow this link;

Blue Agate from Mexico, polished & rough.

Montana Moss Agate--A Great Rock to Tumble

Montana Moss Agate is famous for the "moss" patterns inside the clear to milky agate. The "moss" isn't really moss but water deposits. They form as black fern-like or tree-like patterns that resemble moss.

Often there is some redish to brownish banding. When you have both the moss and the banding it is quite spectacular. Unfortunately there isn't much you can tell from the outside.

These agate nodules are pretty bland on the outside. It's the inside you get excited over.

You can see a sample and order at Montana Moss Agate Tumbling Rough.

The Story Behind Candy Jasper

It was discovered about 3 miles off the coast of Madagascar under the ocean. The miners have to take small boats, like bass boats, out during the receding tide and wait for the boats to sink on the ocean floor. Then they fill the boats up with as much of the Candy Jasper as they can and wait for the incoming tide to ship the rock back to shore. Because of the unusual circumstances involving this unique gem, only limited amounts will be available as they can only do this mining process for about 4 -6 months (or less ) of the year due to monsoons and weather.

We have tumbled several batches ourselves and we can't keep it in the store as it takes an incredible shine.

Here's how to polish it:
Run it in the step 1 coarse grit for 1-2 cycles. We like ours well rounded so we run it for 1 week then change it all out and start it over again in the step 1. Then do it the same as you would any other agate. Make sure you put the plastic pellets in with the polish.