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 1 
 on: December 13, 2018, 07:25:05 PM 
Started by VegasJames - Last post by VegasJames
Re: "Porcelain" jasper (as a type due to grain). The only jasper I've heard everyone agree on is Willow Creek Jasper. Some also include Morrisonite.
The term "Porcelain jasper" has a long history, going back to at least the 18th century in old mineralogy books I've read. It was distinguished from "Common jasper" by its greater silica content, slightly greater hardness, ability to fuse under high heat, its comparative tendency to shatter more easily (more like glass), generally greater weight, shinier fracture. It also took to burnishing (i.e., by rubbing the stone against itself back in the days before modern polishes), and producing a higher polish more readily than those considered in the "Common jasper" category. Most of the "Porcelain jaspers" described in early literature came from Europe and Asia. Back in the 1950s and 1960s, these were still the characteristics denoted by the term when it began to be applied to jaspers in western North America: Morrisonite, Deschutes, Imperial, and later, Willow Creek. The term started getting applied to just about anything in the 1990s (blame JTV, ebay, etc.). That doesn't mean that there aren't others that fit the old definition discovered since (I'd say Bruneau likely qualifies), but most newer material now getting that label slapped on does not (including the "Porcelainite" from Mexico).

The "ring test" was one of the initial tests used by old-timers to distinguish (Porcelain jasper can ring like fine crystal when lightly tapped, shards tinkled like a crystal chandelier when striking each other and sound like a breaking window when dropped and shattering).  It is inconceivable that every piece from a given deposit has ever met the "Porcelain" designation, either, but was a general characteristic of material from those sources.

Perhaps in this age of diamond and other hard, super-fine polishes, the distinction is less useful. Some people can get a mirror shine from just about anything these days.

Thanks for the extra information. I noticed the sound difference just a little while ago. I have someone who buys rocks from me and he was here a few hours ago. When I went to put  crate of the Lahontan jasper away heard that glass-like sound when I put the crate down.

The jasper is very different than other jaspers I have collected. One characteristic again is a very slick and shiny surface in the raw.

 2 
 on: December 13, 2018, 07:06:05 PM 
Started by VegasJames - Last post by rocks2dust
Re: "Porcelain" jasper (as a type due to grain). The only jasper I've heard everyone agree on is Willow Creek Jasper. Some also include Morrisonite.
The term "Porcelain jasper" has a long history, going back to at least the 18th century in old mineralogy books I've read. It was distinguished from "Common jasper" by its greater silica content, slightly greater hardness, ability to fuse under high heat, its comparative tendency to shatter more easily (more like glass), generally greater weight, shinier fracture. It also took to burnishing (i.e., by rubbing the stone against itself back in the days before modern polishes), and producing a higher polish more readily than those considered in the "Common jasper" category. Most of the "Porcelain jaspers" described in early literature came from Europe and Asia. Back in the 1950s and 1960s, these were still the characteristics denoted by the term when it began to be applied to jaspers in western North America: Morrisonite, Deschutes, Imperial, and later, Willow Creek. The term started getting applied to just about anything in the 1990s (blame JTV, ebay, etc.). That doesn't mean that there aren't others that fit the old definition discovered since (I'd say Bruneau likely qualifies), but most newer material now getting that label slapped on does not (including the "Porcelainite" from Mexico).

The "ring test" was one of the initial tests used by old-timers to distinguish (Porcelain jasper can ring like fine crystal when lightly tapped, shards tinkled like a crystal chandelier when striking each other and sound like a breaking window when dropped and shattering).  It is inconceivable that every piece from a given deposit has ever met the "Porcelain" designation, either, but was a general characteristic of material from those sources.

Perhaps in this age of diamond and other hard, super-fine polishes, the distinction is less useful. Some people can get a mirror shine from just about anything these days.

 3 
 on: December 13, 2018, 06:51:52 PM 
Started by Stonemon - Last post by 55fossil
    I love the reds.....  sweet

 4 
 on: December 13, 2018, 06:40:08 PM 
Started by Stonemon - Last post by lithicbeads
The essence of Trent. So many beautiful stones just go away like Trent.

 5 
 on: December 13, 2018, 05:57:17 PM 
Started by VegasJames - Last post by VegasJames
Re: "Porcelain" jasper (as a type due to grain). The only jasper I've heard everyone agree on is Willow Creek Jasper. Some also include Morrisonite.
The hardest toughest jasper I've ever seen is Polychrome Jasper which destroys diamond saws.

 :dontknow:

 But is Polychrome ever marketed as "Porcelain?"
And how do you measure the level of "fine grained" to separate a "Porcelain" jasper from a non porcelain jasper?

There are several jaspers I gave seen categorized as porcelain jaspers including Dead Camel.  What I have found personally is that these jaspers have a much slicker feel than regular jasper, even more than opal, and I have tumbled some without any grit or polish and the stones are taking on a very high polish. Something I have not found with other jaspers. So there is obviously some type of difference in structure.

As for the grain this should be observable with microscopy.  Electron microscopy showing the differences between the jaspers would be really interesting.

 6 
 on: December 13, 2018, 05:48:39 PM 
Started by VegasJames - Last post by VegasJames
Vegas, this ain't about your thoughts. It is about what I see as common practice today... which really screws up novices and buyers.

BC JADE:   There are dozens of location names as well as accepted Trade names such as Polar Jade. There is an opal from Spencer, Idaho which is named Ice Cream Opal.

    So many people call there jaspers porcelain it is a worthless term. I have yet to find the term defined for jasper in any reputable book with a scientific notation.

   I do not try and define what is correct and what everyone else should do. I do state what I find, in my opinion, to be common practice. Some of those practices bother me.

Again if the jade is from different locations within the same region and has different characteristics I don't see a problem with different names. Just like all the jaspers from California do not have the same name. There are MANY DIFFERENT  types of jasper found in the same region called California.

As for your reference to ice cream opal from Idaho this backs my point about the confusion multiple names for the same material causes since the same name can be applied to different stones leading to confusion. In this case the name ice cream opal also being applied to Tiffany stone.

And speaking of Tiffany stone can you show me any term defining Tiffany stone from a reputable book with a scientific notation? I doubt it. So does that mean Tiffany stone does not exist?

 7 
 on: December 13, 2018, 04:25:56 PM 
Started by Stonemon - Last post by Stonemon
A piece off the end of a chunk I slabbed today.
30x19x6 mm
Had good color so I made a bead.

 8 
 on: December 13, 2018, 04:14:11 PM 
Started by VegasJames - Last post by finegemdesigns
Re: "Porcelain" jasper (as a type due to grain). The only jasper I've heard everyone agree on is Willow Creek Jasper. Some also include Morrisonite.
The hardest toughest jasper I've ever seen is Polychrome Jasper which destroys diamond saws.

 :dontknow:

 But is Polychrome ever marketed as "Porcelain?"
And how do you measure the level of "fine grained" to separate a "Porcelain" jasper from a non porcelain jasper?

 9 
 on: December 13, 2018, 02:28:24 PM 
Started by VegasJames - Last post by 55fossil
Vegas, this ain't about your thoughts. It is about what I see as common practice today... which really screws up novices and buyers.

BC JADE:   There are dozens of location names as well as accepted Trade names such as Polar Jade. There is an opal from Spencer, Idaho which is named Ice Cream Opal.

    So many people call there jaspers porcelain it is a worthless term. I have yet to find the term defined for jasper in any reputable book with a scientific notation.

   I do not try and define what is correct and what everyone else should do. I do state what I find, in my opinion, to be common practice. Some of those practices bother me.

 10 
 on: December 13, 2018, 07:29:25 AM 
Started by lapidaryrough - Last post by lapidaryrough
From Calipooa river Holley Oregon. From the land Holley Oregon pre-1984. Bill Belveal Barn site. over 40,000 lbs. of hidden rock, till 1984 barn fire.

Palm wood in Oregon?

 grape vine, the root i have to find, its misplace in a cash spot lost.

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