FMF - Friends of Minerals Forum, discussion and message board

[Dennis Beals]

The very intense red grossular in very white matrix are from the Cerro de Moka, Sierra de Cruces, Mun. de Sierra Mojada, near Hercules, Coahuila, Mexico

This is a bluff a few kilometers to the southwest of the Santo Domingo Claim, Sierra de Cruces, Mun. de Sierra Mojada, near Hercules Coahuila. This is the locality with the black cores in a scapolite / wollastonite matrix and was first developed by Benny Fenn from 1995 - 2000.

The classic green and light pink garnets that were labeled Lake Jaco are found several kilometers to the northeast in decomposed matrix on the Alicante Ejido ranch, Sierra de Cruces, Mun. de Sierra Mojada,near Alicante, Coahuila, Mexico

This series of skarn deposits are hosted in a curving arc of hanging roof pendants on the southeast flank of the Sierra de Cruces.

Recent work on the Santo Domingo claim involved cleaning out the original hole, removal of overburden and then reversal of direction. The latest work has followed into an area with more massive vesuvianite matrix and less quartz. This allowed for larger crystals and more intense color. Less calcite in this area makes preparation much more difficult.

Good crystals of vesuvianite are relatively scarce as they tend to be very fragile.

[Jordi Fabre]

Hi Dennis, welcome here!

Dennis carries with him PLENTY of amazing histories related with the mineral collecting in Mexico. We will be very lucky if he can find time and share them with us...

Welcome again Dennis.

Jordi

[GneissWare]

Hey, Dennis,
Nice to see you here!!!

You give a specific locality for the big pink, George Burnham era garnets. Have you actually visited it? We (Casey Jones, Graham Sutton and me) could never find it, even with Burnham's notes.

See you in Tucson, and bring me some unprepped stuff...maybe I'll bring you a gift too.
Bob

[Dennis Beals]

Hello to Everyone here

I have been a lurker here for a long time and as I have been doing more writing lately decided to join in the conversation.

I have not looked for the big pink locality as it is on a different ranch. The series of garnet localities stretch over a large area. The big pinks do not come from the Sierra de Cruces ranch and that only leaves the Alicante Ejido ranch.

This is a very rough area full of mesquite, cactus, ocotillo, scorpions and rattlesnakes. Finding an old picked over outcrop is problematic. One of the local vaqueros (cowboys) is looking into it for me.

Dennis

[GneissWare]

Is that Miguel? Or Luis?

[Peter Megaw]

Denis...you mention vesuvianite only in passing. I have seen at least two distinct styles (pictured below)...the older style being large blocky cloudy yellow-green crystals, with dominant prism faces...sometimes approaching pseudo-cubic as in the picture...sometimes with a well developed dipyramid. I have seen these up to about 10 cm long. These often have multiple sub-faces giving them a scaly appearance. Rarely these are studded with small yellow garnets and sometimes the yellow garnets are studded with small vesuvianites. Are these Alicante? The other style...more recent I think...has smaller crystals (4 cm is max I've seen) with both well-developed prism and dipyramids, smoother sides and a browner gemmier coloration...often very lustrous. There are 2 pictures of these...one I think I got from you. Can you park a better locality than Sierra Las Cruces on these?

I also have one sample with copper oxide coatings...this seems rare to me, and when I have explored in the area that entire skarn looks very dry as far as metallic mineralization is concerned. There is a similar skarn in northern Chihuahua...east of Villa Ahumada...where there are highly elevated REEs in a zinc-rich fluorite-cemented breccia about 1 km in diameter...any hints of high REEs at Cruces? Has anyone looked?

[GneissWare]

Peter,

There are many colors and habits of vesuvianite present in the huge skarn. Like the garnets, which display a variety of colors depending on which outcrop they are found, the vesuvianites are similar, except there are more outcrops lacking vesuvianite than having it present. I have large blocky yellow vesuvianites associated with grey garnets collected on outcrops crossing the road leading into the ranch. I have deep green vesuviantite found with hot pink and lavender garnets, and of course the yellowish ones asscociated with the pink garnets Dennis currently working.

The blocky ones you first mention are found in several outcrops as I recall without looking at the topo map where I recorded the locales for various colors when I collected there over a 3 year period in the early 1990s.

Bob

[Jordi Fabre]

[Dennis Beals]

Peter

The first picture of vesuvianite you posted shows what is currently coming out with somewhat better crystals occasionally coming out. They tend to be rather fractured and fall apart. Good combos are rare.

I believe that the second photo of the "new" style is one that came from me. It came from Keith Williams and had one of the Lake Jaco, Morelos mashup labels. None of these were seen when Benny Fenn worked there.

In talking with one of the vaqueros from the ejido Alicante they don't get many good vesuvianites now where they working.

Dennis

[Elise]