Shark, Ray, And Fish Micros From The Txi Quarry Texas

[MarcoSr]

I just finished searching some matrix from the TXI Quarry, Midlothian, Johnson Co., Texas from the Cretaceous, Coniacian, Austin Group, ATCO Formation. The vast majority of the teeth were heavily reworked with heavy wear and damage. However, I did find some nice and interesting shark, ray, and fish micros. I’m posting some of the nicer and more unusual micros. Most of the specimens were in the 1mm to 5mm size range. If you place your cursor on a JPEG image you will see the file name which will have the specimen id as best that I can determine and the specimen size. Each matrix that I search makes me more of an avid micro tooth collector. If anyone has or can collect good matrix with shark, ray, and fish micros please send me a PM.

Marco Sr.

Edited May 1, 2015 by MarcoSr

[Fossildude19]

Marco,

Thanks very much for posting these threads - I am in awe of your photography of these miniscule specimens.

I have really been enjoying them.

Regards,

[masonboro37]

Ahhh, splendid finds and great pic's of them. I am a micro gastropod collector and your micro's are amazing! I need to start collecting micro shark and ray material!

[Just Bob]

Very cool and interesting teeth! I really like the drum fish mouth plate.

I know you said Cretaceous but do you know the exact age of the fossil shown?

[MarcoSr]

Marco,

Thanks very much for posting these threads - I am in awe of your photography of these miniscule specimens.

I have really been enjoying them.

Regards,

I take a lot of pictures each week of micros for my family website and for documentation of what I found from a site. So taking the pictures has become second nature. I'll probably be posting more sites as time goes on. I'm constantly searching matrix from new sites. I have micros now from close to 100 sites worldwide.

Marco Sr.

[MarcoSr]

Ahhh, splendid finds and great pic's of them. I am a micro gastropod collector and your micro's are amazing! I need to start collecting micro shark and ray material!

There are a good number of collectors worldwide who bring home matrix from sites with shark and ray material. Since I won't get to most of these sites in person, matrix allows me to search the site fauna from home. The awesome diversity of shark and ray micro material really makes collecting it worthwhile. I've only seen micro gastropods in matrix from one Cretaceous and one Eocene site in Texas but that is because I'm looking for shark and ray material matrix. If you haven't already, you might PM silverphoenix and see what matrix he may have with micro gastropods.

Marco Sr.

[MarcoSr]

Very cool and interesting teeth! I really like the drum fish mouth plate.

I know you said Cretaceous but do you know the exact age of the fossil shown?

The ATCO Formation is Cretaceous, Coniacian and is right at the Turonian boundary. The Turonian ends and the Coniacian begins around 89.8 million years ago. So the fossils which are not reworked are around 89 million years old. A lot of the fossils however are reworked from the Turonian so they would be older.

Marco Sr.

[mikecable]

MarcoSr

Did you process the matrix yourself? I've got about 30 kilograms of bulk, chunk matrix I collected a few months ago, and it's a booger to process. Any tricks?

[Auspex]

I take a lot of pictures each week of micros for my family website and for documentation of what I found from a site. So taking the pictures has become second nature. I'll probably be posting more sites as time goes on. I'm constantly searching matrix from new sites. I have micros now from close to 100 sites worldwide.

Marco Sr.

You have enriched the Forum experience for all members (and no doubt many more who are not) with your efforts. Just speaking for myself, I enjoy your posts immensely: the information therein is all new ground for me. Thank you.

[MarcoSr]

MarcoSr

Did you process the matrix yourself? I've got about 30 kilograms of bulk, chunk matrix I collected a few months ago, and it's a booger to process. Any tricks?

Unfortunately I do have to process a lot of different matrix. Processing it really depends on what materials the matrix is composed of and cemented with and what fossils you are looking for. Phosphatic fossils like shark and ray teeth will survive water, H2O2, and low concentrations (5% to 10%) of weak acids like acetic (vinegar) or formic. Do not use stronger concentrations or stronger acids like hydrochloric (muriatic), nitric, myristic, sulfuric etc. They are dangerous to use outside a lab environment without the proper safety equipment and will destroy your fossils. Also if you are looking for forams, ostracodes etc. don’t use any acids at all as they will destroy your fossils. I usually process sand and clay cemented matrixes similarly. You want to get them completely dry. I sun dry everything. Some folks use ovens or microwaves to dry matrix. If you get the temperatures too high especially in a microwave you can bake clay based matrixes (like baking pottery) and make them almost impossible to break down. Once fully dry I then put the matrix in hot water in a 5 gallon bucket or pour boiling water on it in a 5 gallon bucket. Let the matrix sit for a day or so. If the matrix pieces become real soft I very gently manually break them up with my hands. Be careful with this as you can damage the teeth. I repeat the drying and water as necessary. Some people have had success using Kerosene to speed up the process. Kerosene has never worked for me and only made my front porch and matrix smell really bad. Some people have success using detergents like TSP. I have only had limited success using TSP on sand and clay cemented matrixes. Plus when you rinse the matrix to remove any residual chemicals you get a lot of suds which makes the process very time consuming. Small amounts of sand based matrix can be broken down using 3% H2O2 or the teeth can be cleaned of matrix in H2O2. Don’t use 30% lab grade H2O2 unless you have a lab environment and all the associated safety equipment. It is dangerous to use. Some people just soak sand or clay based matrix for weeks or months in water. I don’t have the patience for this. Carbonate cemented chalk, quartz sandstone, limestone, siltstone, claystone and some shale can be broken down with vinegar or formic acid and combinations of freezing, boiling, simmering etc. If you just leave the matrix in vinegar, it can take weeks or months with multiple vinegar changes to break down matrix or only partially break matrix down. Cycles of freezing the matrix, pouring boiling vinegar on the matrix and letting it sit and then simmering the matrix on a hot plate outside your house can speed up the process or help with matrix that won’t break down just sitting in the vinegar for long periods of time. Always rinse your matrix really well in water to remove any acid that may still be in it after final processing. You can clean small amounts of matrix from teeth by putting them in vinegar. But be careful. Even though vinegar doesn’t seem to bother the teeth when breaking matrix down, a few teeth in a jar of fresh vinegar can cause the teeth to lose their gloss or even discolor them if left in the vinegar for more than a few hours. There are several industrial detergents that will break these matrixes down especially shale but I won’t even name them as they are very dangerous to use outside a lab environment without safety equipment. Some matrixes can only be broken down by mechanical means. Strong use of hand twisting or even tapping or hitting with a hammer can break some down. Obviously the fossils take a beating with mechanical methods. Mechanical methods can work OK when you are looking for Forams, Ostracodes etc., can’t use chemicals or find another method to break down the matrix and there are lots of them in the matrix which will survive the mechanical damage. Visible fossils can be exposed with scribes and other air abrasion tools. Bottom line, every matrix is different. Depending on the materials and with trial and error hopefully you can devise a method that works for that matrix. If you are not sure of the matrix material or what is cementing the matrix, start with drying and water as both vinegar and H2O2 use can get expensive if a lot is needed and you don’t want to waste money if they aren’t really needed.

Marco Sr.

[MarcoSr]

You have enriched the Forum experience for all members (and no doubt many more who are not) with your efforts. Just speaking for myself, I enjoy your posts immensely: the information therein is all new ground for me. Thank you.

Now that I am semi-retired I have a lot more time for fossil collecting and searching matrix. Hopefully if I can continue to get new matrix, I will continue to post what I find.

Marco Sr.

[MakoMeCrazy]

Cool finds. Similar stuff in Lee Creek Material.

[Roz]

Just fantastic teeth!! Great images too!

[wfrr]

great finds, i wish my camera could do pics that good too!

[MarcoSr]

great finds, i wish my camera could do pics that good too!

I take the pictures with a digital microscope which works much better than regular cameras or scanners for the micro teeth.

Marco Sr.