RockHoundBlog

Jasper – mineral of the day

Filed under: Mineral of the day,regular postings — Gary January 16, 2008 @ 10:05 am

Jasper is an opaque, impure variety of silica, usually red, yellow or brown in color. This mineral breaks with a smooth surface, and is used for ornamentation or as a gemstone. It can be highly polished and is used for vases, seals, and at one time for snuff boxes. When the colors are in stripes or bands, it is called striped or banded jasper. Jaspilite is a banded iron formation rock that often has distinctive bands of jasper. Jasper is basically chert which owes its red color to iron(III) inclusions.

jasper

Etymology and historical/mythical usage

The name means “spotted stone”, and is derived from Anglo-French jaspre, from Old French jaspe, from Latin iaspidem, the accusative of iaspis, from Greek iaspis, via a Semitic language (cf. Hebrew yashepheh, Akkadian yashupu), ultimately from Persian yashp.

The word yashepheh in the Masoretic text of Exodus 28:20, referring to a stone in the Hoshen, is thus reflected in the Septuagint by the word Iaspis, and usually translated into English as Jasper. Despite the most common form of Jasper being red, scholars think that the yashepheh here actually refers to a green form of Jasper – which was very rare, and so highly prized; the Greeks used Iaspis to refer to the green form, while the red form simply fell under the term Sard – which just means red. Rebbenu Bachya argues that this stone represents the tribe of Benjamin, but there is actually a wide range of views among traditional sources about which tribe the stone refers to.

It is described in the Book of Revelation (21:11) as follows: “It shone with the glory of God, and its brilliance was like that of a very precious jewel, like a jasper, clear as crystal.”

Types of jasper

Jasper can appear as an opaque rock of shades of red due to mineral impurities. Patterns can arise from the formation process and from flow patterns in the sediment or volcanic ash that was saturated with silica to form jasper, yielding bands or swirls in the rock.

Jasper may be permeated by dendritic minerals providing the appearance of vegetative growths. The jasper may have been fractured and/or distorted after formation, later rebonding into discontinuous patterns or filling with another material. Heat or environmental factors may have created surface rinds (such as varnish) or interior stresses leading to fracturing.

A brown jasper that occurs as nodules in the Libyan desert and in the Nile valley is known as Egyptian jasper or Egyptian pebble.

Picture jaspers simultaneously exhibit several of these variations (such as banding, flow patterns, dendrites or color variations) resulting in what appear to be scenes or images in a cut section. Spherical flow patterns produce a distinctive orbicular appearance. Complex mixes of impurities produce color variations. Healed fractures produce brecciated jasper. Examples of this can be seen at Llanddwyn Island.

deschutese_jasper_22

The history of Biggs Jasper, DESCHUTES PICTURE JASPER, Oregon.

Thanks wikipedia

gary-


Willow Creek Jasper

Filed under: how to?,regular postings — Gary @ 9:46 am

Willow Creek Porcelain Jasper
Article written by : Philip Stephenson RareRocksAndGems.com 8/17/07
The intent of this article is to educate the public and not to discredit any individual or organization.

Willow Creek Jasper is one of finest porcelain jaspers in the world. Given the quality of material seen on the Internet, most collectors are not aware of the outstanding qualities of premium material. Willow Creek jasper is mined 15 miles north of Eagle, Idaho. (NW of Boise, Idaho). The Jasper forms in the center of giant thunder eggs and rarely in seams. One of the prevailing theories, as far as Willow Creek goes, is that these thunder eggs formed deep within the earth, then were trusted up through large volcanic vents where they accumulated and solidified surrounded by very hard rhyolite.

Mining the Thunder eggs is very difficult hard rock mining. Dynamite is used to loosen the eggs within the rhyolite matrix and once loosened, next comes the back hoe and pry bar. Once free, the eggs may only be opened by sledgehammer and wedges.

Willow Creek Jasper is known for its subtle pastel colors, streamer patterns, and egg or orb patterns. Premium quality Willow Creek is unmatched. It takes an extreme high gloss… like liquid glass. People who have worked Willow Creek say it has pastel colors and is somewhat soft and delicate in nature…perhaps, but top premium quality Willow has dramatic coloring, and incredible patterning. I consider it the purest porcelain of the porcelain jaspers. The Willow Creek Mine has been producing jasper for the past 35+ years but unfortunately a good deal of low grade is sold on the internet market today.

High grading Willow Creek rough is a little tricky and should only be done by someone with experience with this material or by having the actual rough in your hands to inspect. Low grade Willow is often times sold as “good quality” only to have iron pits and iron stains though the entire piece. The pits are actually tiny iron balls that when cut take on the pit look to them. Anyway, here’s a prime example: Notice the iron pitting and stains within the jasper. Example #1, Example #2, Example #3 . Cabochons with these iron pits are very unattractive and will undercut within the harder jasper surrounding it. Here’s a cabochon that looks more like Chicken Pox, it’s actually iron pits. Example #4.

Still, not all is lost if you happen to get “THE POX” in your rough Willow Creek pieces. Many times you can still work around these bad spots but of course you are limited in your choices of patterns, also there might be a hidden pit just under the surface. In slabs, you can get an idea if there might be a hidden pit by looking at the other side but most often the sellers on Ebay do not have a picture of other side. Example #5. Rust on the other hand there’s no way around it…the area is unusable.

Compared to other fine jaspers, Willow Creek has fewer natural fractures (cracks made by Mother Nature) which makes it more desirable when trying to optimize material losses. The fractures that do exist are typically single fractures and not spidery. Although the area close to the impacts of the hammer normally gets pretty messed up, see this Ebay example: Example #6. Single fractures result from the breaking and wedging open the large thunder eggs. Helpful hint: When trying to buy any rough or slab by a photo it’s always desirable to see the rough/slab item you are buying dry, verses wet. Wet will make any fracture or defect disappear. Here’s a very good example: I found this a few years back out on one of my rockhunting trips. I got very excited about the orbs with the black jasper background. Wet Example #7, Dry Example #7.1. Now, it’s my wife’s favorite stepping stone in her garden.

Now, see two examples of Willow Creek Porcelain Jasper at its most purest. These are now in my Willow Creek Collection. Example #8. Example #9

Buying unproven rough of any kind or finished pieces over the internet should undertaken with extreme caution. Only a few reputable dealers sell excellent Willow Creek Jasper on the Internet including finished pieces, and proven or unproven rough.

(more…)

2 great rockhound domain names are available for purchase- Rockhounds.org and RockHound.info

Filed under: regular postings — Gary January 8, 2008 @ 2:59 pm

Just letting the rockhound community know that these 2 great domains are for sale. They are excellent for a rockhound site as they are very brandable and easy to remember. Dont let them get away :) Just goto the site and click on “email to offer”.

rockhound.info

rockhounds.org

thanks and good luck, Gary.

Morrisonite Jasper

Filed under: regular postings — Gary January 1, 2008 @ 1:19 pm

Phil from RareRocksAndGems.com has wrote some good/interesting articles that I will be posting in the coming weeks. Everyone should check out his site as there (among other things) are some very nice morrisonite specimens like the one below:

morrisonite

Read about the history or morrisonite here- thegemshop.com/morrison4.htm

Here is his first article, enjoy…
morrisonite_specimen

The display of my Morrisonite Collection was complete success! Even very conservative old timers came up and congratulated me on my specimens saying they have not seen this type of colorful old stock in years, let alone the amount.
During the whole two days I sat close to my display so I could see/hear and gage the general public and hard core rock hounds reactions. Needless to say I was very happy and very amused at the comments. Some of the funny one’s were: ” S..T! I think I just pissed my pants!”, “I can’t believe someone owns all this incredible Morrisonite and not made any cabs out of it…I think I’m going to throw-up” and the one I like the most is from one of my rock hound friends “Oh my GOD Philip THAT’S JUST SICK!” That’s just some of the many great comments.
There was great Jasper dealers at the show as always. The mine owner of the Willow Creek mine, Bruneau Jasper mine and the Oregon Carrasite mine. They brought some good stuff and had their own displays too.A moment at the show:
This made up for all four months and staying up to 3 AM almost every night getting them ready.
I was sitting in my chair watching everyone go pass the display when this very old gentlemen stooped and barely walking with a cane on the other side of the isle looked up and saw my sign that said: Morrisonite” THE KING” of Jaspers. He stopped and began shuffling over to my two displays. When he finally stood in front of the displays his shaky hands reached up and took off his glasses which he began to clean, he put them back on and stood looking for about 10 to 15 minutes as people looking at the displays moved around him. Finally he reached into his back pocket and pulled out a handkerchief and began to wipe his eyes. Looks like he was crying! seeing this I got up from my chair and approached him saying: “Do you like Morrisonite?” he looked up at me with red teary eyes and said in a rough voice “I used to have my own Morrisonite collection 30 years ago a lot like yours… but my kids sold them all and then put me in a G-d damm old folks home…now I just look”. It took me a few seconds to recover… but I began asking him various questions about how he made cabs and what type of stuff he had in the past and so on. I even learned a few things myself. After a while his daughter came up… she didn’t look happy and said “Where have you been we have been looking all over for you!” I jumped in and said “OH, he’s OK, we have just been talking rocks”… I don’t think she heard me…she then said to her father “wait right here! I’ll get your chair”. She began to leave and the old man looked up at me and shook his head. He then without speaking slowly turned around and continued to look again at my specimens.
After a while his daughter (in a huff) finally showed up with the wheelchair and began guiding him into it. I felt really sad for the old guy and I began to have thoughts of my own father getting close to that age too. She began wheeling him away just a few feet and stopped when she saw her husband across the tables and waved to him, but he did not see her waving, she then told her father she’ll be back and if I could watch him for a second while she gets her husband, I said “yes, no problem”…she walked away got her husband and began walking back…I quickly open my case and grabbed one of my golf ball sized specimens placed it into his hand and whispered in his ear…”hold on to this one”…. he opened his hand and looked up at me with gleaming eyes and mouthed a slow thank you. He looked away just in time to see his daughter almost there, he quickly closed his hand around it and took his other hand in mine and gently squeezed it. I said my good byes as he rolled off. It made it all worth it.
Cheers!
Philip-
(Here is the article link for all the pictures)

Thanks Philip,

gary-