rocks and minerals

[strange stones 1]

Hello every one, i am new on this forum and i found many rocks and other minerals here in the Netherlands EU. The first mineral is like glassy looks, but i receive that on the side of it there are a structure if you see, and it goes from square to triangle how is that possible ? Then on the other picture you see the skin of this mineral, i do that with some Diamond pasta on a drill brush for hobbyist a dremell tool. now the reason why i do this, because i do this also on a piece of glass and see the different between the result of it, glass will look like milky, but this mineral you can see is like it hold together and dont let go of. Also with a Diamond drill head and make a line or curve on it, glass is very splintery and this mineral don"'t splintery also no dust get off.

Photo nr.1 this is the mineral where i talk aboud it. Also you can see on one side there are some crow lines on it stepp likes picture 2, 4, 6, 7, and on photo 8.

Square to triangel are on photo, 5, 9, 10,11, and 12. 

Skin like are photo, 14, and 15. Its meets 3cm long, 2cm wide, 2 and a halfcm hight. Its weight 16,4gr. 

[Au Seeker 2,184]

Welcome to the forum Strange Stones!

I am moving your topic to the "Rocks, Minerals and Fossils" section so more members will see it and possibly be able to help you with an ID.

[d_day 117]

It's glass. 

[strange stones 1]

On ‎12‎/‎5‎/‎2018 at 2:39 AM, d_day said:

It's glass. 

Hai D Day, thanks to answer me but how sure you are aboud this did you see that sharp triangel right in the corner well i see that same sign also on a photo of a rough diamond it has be the same sign. I no that most rough shapes have trigons on or inside it but not on irregullar shapes. 

[d_day 117]

2 hours ago, strange stones said:

Hai D Day, thanks to answer me but how sure you are aboud this did you see that sharp triangel right in the corner well i see that same sign also on a photo of a rough diamond it has be the same sign. I no that most rough shapes have trigons on or inside it but not on irregullar shapes. 

I see nothing here that indicates diamond. There's an easy way to test it though. Do a scratch test. If something harder than glass but softer than diamond scratches it, then you have glass.

[adam 2,228]

I woudnt think a diamond would have cleavage? That item cleave`s like glass

[Morlock 790]

1 hour ago, adam said:

I woudnt think a diamond would have cleavage? That item cleave`s like glass

Diamonds have cleavage. That's what they depend on when they break down large carat stones.

[Saul R W 725]

When I was a youngster and fresh back to the States after living outside the country since infancy, I discovered a coal and diamond deposit next to and under an old school building in Arizona.  The deposit consisted of dime-sized chunks of coal, which I correctly identified, and many small diamonds, some with perfect clarity, and others with either green or blue impurities.  The incorrectly identified "diamonds" even scratched glass, which I proved on the windows of my mother's home (undiscovered until later).

I let my best friend in on the secret, drew up a 60-40 contract in my favor (he would recieve 40 Red Ryder wagonloads of diamonds for each 60 wagons of loot I took home), and we began excavating, straight down five or six feet, and then under the school's footings.  

School was out for the summer, so it took a while before we were caught and accused of attempted sapping of one of Prescott's historic buildings.  By that time, the hole was large enough for two kids to work side by side, and we were long past the old stem wall and well on our way to tunneling entirely under and beyond a rear corner of the building.  

It turned out I'd located the school's old ash dump, which contained a considerable amount of unburned coal and a lot of crushed bottle glass.  The police officer (who was already familiar with me, and would become more familiar in coming years) tasked with investigating explained to me that an addition to the school had buried the old dump.  Back when he attended that school, before the addition was built, kids would line bottles up on the ash dump and practice rock throwing, which was sanctioned by teachers as long as the glass was broken into small enough pieces to not be too hazardous to bare feet.

Point being, I learned early that not everything that's hard, clear and sparkly is a diamond.  Also, that it's important to understand history (human, geological, and sometimes both) to understand what you've found today.  In your case, the Netherlands have a well-documented history of glassmaking, and parts of your country must almost be paved with the offal of that craft, so if you find a hard, clear, sparkly near-surface specimen there, think glass, not diamond, especially if the specimen far outweighs the largest unflawed diamond ever found anywhere on the planet.  Reality can be a bugger, especially if it clashes with hopeful but erroneous presumptions, but experiencing dashed hopes can be an important part of learning.  Or not.  That really is a pretty hunk of glass.

[hardtimehermit 156]

Saul, i would not be surprised if you had dug all the way to the secret underground tunnel of Prescott. If you have been down there i hope we hear a story some day. I lived in Prescott from 95 to 2000 and always thought the tales of the tunnels under Prescott were cool. I bet there's some pretty glass down there, just like the piece we are talking about.

[hardtimehermit 156]

39 minutes ago, Saul R W said:

When I was a youngster and fresh back to the States after living outside the country since infancy, I discovered a coal and diamond deposit next to and under an old school building in Arizona.  The deposit consisted of dime-sized chunks of coal, which I correctly identified, and many small diamonds, some with perfect clarity, and others with either green or blue impurities.  The incorrectly identified "diamonds" even scratched glass, which I proved on the windows of my mother's home (undiscovered until later).

I let my best friend in on the secret, drew up a 60-40 contract in my favor (he would recieve 40 Red Ryder wagonloads of diamonds for each 60 wagons of loot I took home), and we began excavating, straight down five or six feet, and then under the school's footings.  

School was out for the summer, so it took a while before we were caught and accused of attempted sapping of one of Prescott's historic buildings.  By that time, the hole was large enough for two kids to work side by side, and we were long past the old stem wall and well on our way to tunneling entirely under and beyond a rear corner of the building.  

It turned out I'd located the school's old ash dump, which contained a considerable amount of unburned coal and a lot of crushed bottle glass.  The police officer (who was already familiar with me, and would become more familiar in coming years) tasked with investigating explained to me that an addition to the school had buried the old dump.  Back when he attended that school, before the addition was built, kids would line bottles up on the ash dump and practice rock throwing, which was sanctioned by teachers as long as the glass was broken into small enough pieces to not be too hazardous to bare feet.

Point being, I learned early that not everything that's hard, clear and sparkly is a diamond.  Also, that it's important to understand history (human, geological, and sometimes both) to understand what you've found today.  In your case, the Netherlands have a well-documented history of glassmaking, and parts of your country must almost be paved with the offal of that craft, so if you find a hard, clear, sparkly near-surface specimen there, think glass, not diamond, especially if the specimen far outweighs the largest unflawed diamond ever found anywhere on the planet.  Reality can be a bugger, especially if it clashes with hopeful but erroneous presumptions, but experiencing dashed hopes can be an important part of learning.  Or not.  That really is a pretty hunk of glass.

 

[Saul R W 725]

38 minutes ago, hardtimehermit said:

Saul, i would not be surprised if you had dug all the way to the secret underground tunnel of Prescott. If you have been down there i hope we hear a story some day. I lived in Prescott from 95 to 2000 and always thought the tales of the tunnels under Prescott were cool. I bet there's some pretty glass down there, just like the piece we are talking about.

I have been in the old tunnels honeycombing downtown.  My stepfather remodeled the Palace, Brownlow's Department Store, AZ General Supply, and several other buildings within a couple blocks of the courthouse when I was a kid, and I explored.  From the basements, it was possible to travel for many blocks without surfacing, including under the courthouse (I'm certain someone has gated the tunnels for security reasons by now).  There were rooms under both the plaza and Whiskey Row filled with narrow bunks, old opium dens and lodging for both Chinese workers and hookers.  The first time I started wandering around down there, my younger brother and I eventually emerged from a storm sewer at the old high school (now a middle school, I think).  And yes, the whole complex was filled with artifacts.

Edited Thursday at 04:25 PM by Saul R W
Typo

[Saul R W 725]

An addendum, hardtimehermit:  I failed to mention that the old opium dens had not been entirely abandoned at the time I was growing up in Prescott.  The Yavapai County DA and his assistant, along with several county and city lawmen, prominent downtown businessmen, and my stepfather and his employees, used to smoke pot down there.  It was the late 60s and early 70s, so not too surprising to round a bend in the labyrinth to find a community pillar in a cloud of his own making under his store or office.  The world changes, but not much.

[Morlock 790]

5 hours ago, Morlock said:

Diamonds have cleavage. That's what they depend on when they break down large carat stones.

 

[hardtimehermit 156]

Thanks for sharing Saul, you are truly an O.G. rascal from the old school. 

[Saul R W 725]

4 hours ago, hardtimehermit said:

Thanks for sharing Saul, you are truly an O.G. rascal from the old school. 

Sooooo old school, I had to Google "O.G." to figure out what in the heck you were talking about.  Not many gangstahs in my clan, but the few who do go that way are the baddest of the bad, unfortunately.  

[pairadiceau 84]

Thank you Wikipedia, "Conchoidal fracture",  one of very few terms I remember from Physical Geology decades ago......

From Wikipedia, the free

Conchoidal fracture

 

 

 

 

Obsidian gives conchoidal fractures

 

Conchoidal fracture in obsidian

 

Conchoidal fracture in flint

 

Conchoidal fracture in glass

Conchoidal fracture describes the way that brittle materials break or fracture when they do not follow any natural planes of separation. Mindat.org defines conchoidal fracture as follows "a fracture with smooth, curved surfaces, typically slightly concave, showing concentric undulations resembling the lines of growth of a shell".^[1] Materials that break in this way include quartz, chert, flint, quartzite, jasper, and other fine-grained or amorphous materials with a composition of pure silica, such as obsidian and window glass, as well as a few metals, such as solid gallium.

Conchoidal fractures can also occur in other materials under favorable circumstances. This material property was widely used in the Stone Age to make sharp tools, and minerals that fractured in this fashion were widely traded as a desirable raw material.

Conchoidal fractures often result in a curved breakage surface that resembles the rippling, gradual curves of a mussel shell; the word "conchoid" is derived from the word for this animal (Ancient Greek: κογχοειδής konchoeidēs < κόγχη konchē).^[2][3] A swelling appears at the point of impact called the bulb of percussion. Shock waves emanating outwards from this point leave their mark on the stone as ripples. Other conchoidal features include small fissures emanating from the bulb of percussion.

They are defined in contrast to the faceted fractures often seen in single crystals such as semiconductor wafers and gemstones, and the high-energy ductile fracture surfaces desirable in most structural applications.^{[citation needed]}

Jump to navigationJump to search

This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed.  (December 2009) (Learn how and when to remove this template message)

Obsidian gives conchoidal fractures

Conchoidal fracture in obsidian

Conchoidal fracture in flint

Conchoidal fracture in glass

Conchoidal fracture describes the way that brittle materials break or fracture when they do not follow any natural planes of separation. Mindat.org defines conchoidal fracture as follows "a fracture with smooth, curved surfaces, typically slightly concave, showing concentric undulations resembling the lines of growth of a shell".[1] Materials that break in this way include quartz, chert, flint, quartzite, jasper, and other fine-grained or amorphous materials with a composition of pure silica, such as obsidian and window glass, as well as a few metals, such as solid gallium.

Conchoidal fractures can also occur in other materials under favorable circumstances. This material property was widely used in the Stone Age to make sharp tools, and minerals that fractured in this fashion were widely traded as a desirable raw material.

Conchoidal fractures often result in a curved breakage surface that resembles the rippling, gradual curves of a mussel shell; the word "conchoid" is derived from the word for this animal (Ancient Greek: κογχοειδής konchoeidēs < κόγχη konchē).[2][3] A swelling appears at the point of impact called the bulb of percussion. Shock waves emanating outwards from this point leave their mark on the stone as ripples. Other conchoidal features include small fissures emanating from the bulb of percussion.

They are defined in contrast to the faceted fractures often seen in single crystals such as semiconductor wafers and gemstones, and the high-energy ductile fracture surfaces desirable in most structural applications.[citation needed]

 

 

[adam 2,228]

Yep , I will have to retract my statement earlier. The Conchoidal fracture after looking it up actually is pretty common , thus proving that I have no idea what i`m talking about.

[Bedrock Bob 1,524]

Cleavage and fracture are two different things. Cleavage planes are weak bonds in the rock. They often follow the crystalline pattern. Fracture is how a mineral breaks between (or without) those cleavage planes.

All silicates have a conchoidal fracture. That is how you shape (or knap) an arrowhead by controlling the conchoidal fracture. They can also have cleavage along planes, like a quartz crystal or a moonstone. These are good examples of minerals who have both defined cleavage planes and a conchoidal fracture.

You can compare this with minerals like obsidian and most agates that have no cleavage planes but have a conchoidal fracture. Petrified wood often has cleavage planes along the original wood grain but also has a conchoidal fracture.

I would say the specimen in the photo has no cleavage and a conchoidal fracture.