FMF - Friends of Minerals Forum, discussion and message board

[Antonio Alcaide]

Could you help me with these flattened titanites?. They come from Gandab Valley (Gandahab), Mohmand Agency, Pakistan. I have seen and bought them in the market but only from one dealer from Pakistan. He is a serious and reliable seller.

But, a few days ago, a friend pointed out these crystals could have been cut. I have not seen them on Mindat where the locality is not recorded.

I post several pictures. The crystals are completely included with chlorite. Instead of the usual wedge shape of the titanite, these are flat and slim. My opinion is that we have here an odd habit of titanite, but natural habit.

Regards

[John S. White]

They are perfectly natural. I have a similar one that is alleged to be from Gilgit, Skardu, that I acquired in 2002.

[Antonio Alcaide]

Thank you very much, John, for your quick answer. It is a pity these uncommon crystals are not recorded on Mindat and elsewhere as far as I know. I checked all the Pakistani titanites from Mindat and I did not see any of them.

Regards

[Maggie Wilson]

Hello, folks

We acquired one of these crystals - actually, it's next on my list of items to photograph and upload to Mindat.

The locality is Shalman Area, Kyber Agency, FATA, Pakitsan.

Under the scope, crystal inclusions and offsets are clearly visible poking up from the surface of the crystal. Conclusion: natural, not cut.

All the best
Maggie

[Carles Curto]

Flattened crystals of titanite are not specially unusual. Goldschmidt figures some drawings and between them, figs. 20 (St. Gottard), 45 (Binnental), 152 (Llach), 230 (Zillertal), 234 (Zlatoust), 854 (Isère) and 326 (Rauris,) are very good examples.

I add some pictures of flattened crystals of titanite (from different localities), their respective thicknesses are not so clear on the pictures, but they are really thin.

[John S. White]

Carles, yours appear to be twinned, in addition to being transparent. Those that Antonio refers to are not twinned and they are not transparent, AND they are usually heavily chlorite-included. Also they are complete floaters, no attachments, no matrix.

[Jesse Fisher]

The last photo that Antonio posted looks to me like it may be a twin. Perhaps need to see a higher resolution or close-up photo to say for sure whether what looks like re-entrant faces at the apex of the crystal are really faces of just a break.

[Antonio Alcaide]

I am very pleased because of your comments.

Maggie, I make a note of the locality you provide. I will check if two localities are close. Your adding of a picture of these titanites to Mindat is a good idea.

I agree with John about the unusual features of these titanites. They are floaters indeed. I must see though the Goldschmidt drawings Carles quoted.

Jesse, looking at the crystal with magnifying glasses I do not see any break. I think the smaller faces could be re-entrant faces but the chlorite and my lackness of knowledge on twins -I mean experience- do not allow me to be categorical. Anyway, I am posting the close-up you asked. I hope it helps.

Regards

[John S. White]

Here is a photo of my titanite. As mentioned it is a complete floater, it is untwinned, there are no re-entrants anywhere around the edges of the crystal, and it is 4.5 cm across. The locality is given as Gilgit, Skardu, Pakistan.

[Tobi]

[Antonio Alcaide]

Another smaller crystal, without attachment point, completely flawless.

Regards

[Carles Curto]

Hi, John.

The Antonio pieces looks also twinned (an aspect not clearly observable on the pictures). The fourth one is clearly twinned and the second and the third show a fine line (with a slight change of shadows) that suggests they are also twinned (the position of the first one make impossible to see anything). Ans yes, they have chlorite inclusions.

The pictures I hanged show a not chloritized crystals, but the basic morphology I can observe, with all the objections that the photography imposes, is very sharp and similar (especially in Kötschatal and Haramosh pieces).

The Antonio pieces looks also twinned (an aspect not clearly observable on the pictures). The fourth one is clearly twinned and the second and the third show a fine line (with a slight change of shadows) that suggests they are also twinned (the position of the first one make impossible to see anything). And yes, they have chlorite inclusions.

The pictures I hanged show a not chloritized crystals, but the basic morphology I can observe, with all the objections that the photography imposes, is very sharp and similar (especially in Kötschatal and Haramosh pieces).

Probably, the most remarkable aspect of the Antonio’s samples is the high degree of thickness and their extreme simplicity of principal forms (interesting).

[John S. White]

I am afraid that I must disagree with Carles. Of course I have not seen these crystals, only the photos Antonio posted, but I can see no twins in the first three and I doubt there is one in the fourth. I also trust Antonio that he can examine the crystals and determine if there are twins there or not. His crystals appear to be virtually identical to mine and there is no twin on mine.

[Antonio Alcaide]

I must apologize for my previous ambiguity. I said "crystals" when I had to say: "crystal". The first four pictures belong to the same titanite in different positions. So I have posted only two crystal, one measuring 5 cm across and the second, smaller enough. Sorry.

As John's titanite is untwinned and both crystals are very similar so it is reasonable to think mine is untwinned too. But, despite of the kindness John's statement about my ability, twins are often beyond my comprehension. I would need a practical tutorial because I usually read about crystallography but it is not enough when handling with twinned crystals.

If it is not twinned, Jesse is right. It could simply display a break at one side.

I am so impressed by this kind of titanites for its extremely even shape. I agree with Carles about it.

Regards

[John S. White]

Antonio: Since you appear to feel that you are unable to recognize a typical titanite twin, I am attaching a photo of such a twin. It is very distinctive. It appears as a V-shaped cut and will always occur along and parallel to the narrow edge of a crystal such as yours, if there is indeed a twin on your specimen. I do not see one in your photos.

[Carles Curto]

[Antonio Alcaide]

Well, I know the typical twin of a titanite, like the example you have posted, John. Obviously there is no V-shaped twin like this on my crystal. Just I thought -as Jesse or Carles pointed- there could be some slightest signs of another kind of twin.

If the V-shaped is the unique twin known for titanite, my crystal is untwinned.

Regards