unknown stone ?
4th Jul 2017 22:37 UTCsunstone sunstone
nearly all of the egyptians do not care with the beach stones whatever they are to the extent that collecting stones is a strange Hobby .
but I do want to know their identity .
Beaches are interesting places. I have a few self-collected items, from the Caribbean barrier reef of Belize and central Texas, through Europe, the Mediterranean littoral, Sri Lanka and on to east Malaysia. The southern and eastern Mediterranean shores are partcularly interesting because one still finds so many small but ancient artefacts in this; relics in this the cradle of European civilisation. Sadly, most found this way are severely damaged and water-worn, past the point where recognition of their original purpose is possible but huge quantities of colourful and banded chalcedony were used for architectural ornamentation in ancient times in Egypt, continuing right through the rise and fall of the Roman Empire.
So my guess is, as Alfred says, mainly varieties of chalcedony. The pieces you show above are interesting because they seem to be translucent, some to absorb strongly blue light and be well suited to ornamental use. However, IMO, there is not a hope of a certain ID without the results from a series of accurately carried out hardness tests and SG determinations. From the little I know of the area, I'd say that what you collect are all that is left of ornamental stonework from the sea-side villas of the rich around Alexandria. If this is so, then the true origin of the mineral(s) will never be known.
On one holiday, lying on the sandy beach in front of my hotel I had the strong impression that, at a certain time of day and with the sun in a certain position, the beach almost seemed to glow. I was curious enough to drop a couple of pinches of this beach sand into a bag and bring it home to put it under a camera and illuminated with a diffused white back-light. Here is what I saw:
Image 1. A small sample of the sand I brought home; dry and sprinkled of a 30mm transparent and colourless polystyrene dish. At this magnification, there's nothing to get excited about,
Image 2. However, selecting, cropping and enlarging a section of the whole image file gives us this!
One day, I shall have some real fun with this sand, testing it out carefully with microscope, polariscope. refractive index testing fluids and a damn good electronic scale and density determination kit. For now, and just from the pic and knowing exactly where the sand came from, I know there is at least one gem mineral present in abundance. To say how many more gem species are present and to calculate the % by mass of each present in my collected sample requires a little more work.
I may not be a rich man - but I know where some riches are! :-) And that's before we get to the octahedral diamond crystal that is still pretty much where it was found, a few hundred metres from the western South Atlantic, that's the size of a hen's egg - and then there's the ametrine site in Canada. And no, I'm not saying where that is either. In each case, the locals prefer to keep their peace, quiet and quality of life as it is. These are truly precious things that money can't buy. Nor even buy my memories of them
Keep looking and finding - but do more testing as well.
So my guess is, as Alfred says, mainly varieties of chalcedony. The pieces you show above are interesting because they seem to be translucent, some to absorb strongly blue light and be well suited to ornamental use. However, IMO, there is not a hope of a certain ID without the results from a series of accurately carried out hardness tests and SG determinations. From the little I know of the area, I'd say that what you collect are all that is left of ornamental stonework from the sea-side villas of the rich around Alexandria. If this is so, then the true origin of the mineral(s) will never be known.
On one holiday, lying on the sandy beach in front of my hotel I had the strong impression that, at a certain time of day and with the sun in a certain position, the beach almost seemed to glow. I was curious enough to drop a couple of pinches of this beach sand into a bag and bring it home to put it under a camera and illuminated with a diffused white back-light. Here is what I saw:
Image 1. A small sample of the sand I brought home; dry and sprinkled of a 30mm transparent and colourless polystyrene dish. At this magnification, there's nothing to get excited about,
Image 2. However, selecting, cropping and enlarging a section of the whole image file gives us this!
One day, I shall have some real fun with this sand, testing it out carefully with microscope, polariscope. refractive index testing fluids and a damn good electronic scale and density determination kit. For now, and just from the pic and knowing exactly where the sand came from, I know there is at least one gem mineral present in abundance. To say how many more gem species are present and to calculate the % by mass of each present in my collected sample requires a little more work.
I may not be a rich man - but I know where some riches are! :-) And that's before we get to the octahedral diamond crystal that is still pretty much where it was found, a few hundred metres from the western South Atlantic, that's the size of a hen's egg - and then there's the ametrine site in Canada. And no, I'm not saying where that is either. In each case, the locals prefer to keep their peace, quiet and quality of life as it is. These are truly precious things that money can't buy. Nor even buy my memories of them
Keep looking and finding - but do more testing as well.
Owen Lewis : many thanks for your kind words and your open mind . you noticed the close relation between the stones and the history of my location . I also noticed that because of the diversity of different kinds of stones in a relativelly small area that makes me know that it was an ancient collection of people lived here ( Egypt ) in the past and was admiring the diversity of stones .
and I repeat your words about the stones :
( used for architectural ornamentation in ancient times in Egypt right through the rise and fall of the Roman Empire.)
also you said : ( what you collect are all that is left of ornamental stonework from the sea-side villas of the rich around Alexandria )
many thanks for you all
and I repeat your words about the stones :
( used for architectural ornamentation in ancient times in Egypt right through the rise and fall of the Roman Empire.)
also you said : ( what you collect are all that is left of ornamental stonework from the sea-side villas of the rich around Alexandria )
many thanks for you all
there is a different patterns of striations looks like some sort of growth lines . absence of conchoidal fractures . the translucency of the stones appear very will when the stones washed with water . I pictured them after washing with water to show the internal structure . there is a type of coral called red sponge coral I think that my stones belong to that type of coral .
sponge coral here : http://coral.org.in/what-is-red-sponge-coral-stone/
sponge coral here : http://coral.org.in/what-is-red-sponge-coral-stone/
I am very grateful for your attention and I know that it is very difficult to identify sponge coral depending on few pictures . sponge coral can be semi translucent to opaque and I think that there is a relation between the degree of translucency and the age of sponge coral stones . I have in my collection all colors and all degrees of translucency starting with the semi translucent to the mature opaque sponge coral ( I think ) .
here is a sample of two mature opaque stones one red and the other black knowing that I have many others .
back side of the stone
here is a sample of two mature opaque stones one red and the other black knowing that I have many others .
back side of the stone
Owen Lewis Wrote:
-------------------------------------------------------
> Reiner Mielke Wrote:
> --------------------------------------------------
> -----
> > The translucency of these is unusual. The only
> > explanation I have is that it is ancient slag.
> > What does one look like broken open? What is
> the
> > specific gravity and hardness?
>
> Reiner, In N.America, your explanation would be
> very likely. But, as said previously, picked off
> an Alexandrian (Egypt) beach, they are most
> likely water-worn architectural rubble that is 500
> - 5,000 years old. Remains from any of several
> earlier civilizations, such can be picked off the
> beaches and shallow waters around much/most of the
> central and eastern Mediterranean. As artefacts,
> these pieces can have no mineralogical
> significance though they may sometimes be of
> archeological interest. Nil commercial value.
>
> As you also suggest, no mineral ID of such rubble
> is possible without patient and accurate testing
> since the locality of find is almost always
> without (mineralogical) significance.
many thanks but I think that rubble or slag cannot be unique and beautiful like that stones ( black sponge coral I think )
-------------------------------------------------------
> Reiner Mielke Wrote:
> --------------------------------------------------
> -----
> > The translucency of these is unusual. The only
> > explanation I have is that it is ancient slag.
> > What does one look like broken open? What is
> the
> > specific gravity and hardness?
>
> Reiner, In N.America, your explanation would be
> very likely. But, as said previously, picked off
> an Alexandrian (Egypt) beach, they are most
> likely water-worn architectural rubble that is 500
> - 5,000 years old. Remains from any of several
> earlier civilizations, such can be picked off the
> beaches and shallow waters around much/most of the
> central and eastern Mediterranean. As artefacts,
> these pieces can have no mineralogical
> significance though they may sometimes be of
> archeological interest. Nil commercial value.
>
> As you also suggest, no mineral ID of such rubble
> is possible without patient and accurate testing
> since the locality of find is almost always
> without (mineralogical) significance.
many thanks but I think that rubble or slag cannot be unique and beautiful like that stones ( black sponge coral I think )
