Sign In Sign Up
  • About
    • Founder’s Statement
    • Leadership
    • Our Purpose & Mission
    • Code of Ethics
    • Bylaws
    • Governance
      • Articles of Formation
      • Board Member Governance
      • Board Activities Timeline
      • Board Elections
      • Conflicts of Interest Policy
      • Financials
    • Advisory Councils
      • Education & Outreach
      • Digital Infrastructure
    • Board Committees
      • Election Committee
      • Membership Committee
    • Major Impact Donors
  • Membership
    • Join Us
      • Educational Form
      • Supporter Form
      • General Member Application
      • Trusted Business Application
    • Add Recommendation
    • Who Can Recommend You
    • Membership Descriptions & Requirements
    • Membership Types
      • Educational
      • Supporter
      • General Member
      • Trusted Business
      • Affiliate
  • Community
    • Our Members
    • Affiliates
    • Quarterly Impact Newsletter
    • Poll(s) – None Active
    • Complaints
  • Benefits
    • Classification
    • Equipment & Products
    • Restoration & Stabilization
  • Standards
    • Best Practices
    • Descriptive Terms
  • Discover Meteorites
    • Authenticity of Meteorites
    • Catalog of Meteorites (CoMets)
    • Educational Resources
    • Galactic Analytics
    • Glossary
    • Meteorite Basics
    • Meteorite Primer for Collectors
    • Advanced Meteoritic Concepts
  • Trusted Businesses
    • All Trusted Businesses
    • Dealers – COMING SOON
    • Products – COMING SOON
    • Services – COMING SOON
  • GMA Store (soon)
    • Shop GMA
    • My Account
    • Cart
    • Checkout
Sign In Sign Up
  • About
    • Founder’s Statement
    • Leadership
    • Our Purpose & Mission
    • Code of Ethics
    • Bylaws
    • Governance
      • Articles of Formation
      • Board Member Governance
      • Board Activities Timeline
      • Board Elections
      • Conflicts of Interest Policy
      • Financials
    • Advisory Councils
      • Education & Outreach
      • Digital Infrastructure
    • Board Committees
      • Election Committee
      • Membership Committee
    • Major Impact Donors
  • Membership
    • Join Us
      • Educational Form
      • Supporter Form
      • General Member Application
      • Trusted Business Application
    • Add Recommendation
    • Who Can Recommend You
    • Membership Descriptions & Requirements
    • Membership Types
      • Educational
      • Supporter
      • General Member
      • Trusted Business
      • Affiliate
  • Community
    • Our Members
    • Affiliates
    • Quarterly Impact Newsletter
    • Poll(s) – None Active
    • Complaints
  • Benefits
    • Classification
    • Equipment & Products
    • Restoration & Stabilization
  • Standards
    • Best Practices
    • Descriptive Terms
  • Discover Meteorites
    • Authenticity of Meteorites
    • Catalog of Meteorites (CoMets)
    • Educational Resources
    • Galactic Analytics
    • Glossary
    • Meteorite Basics
    • Meteorite Primer for Collectors
    • Advanced Meteoritic Concepts
  • Trusted Businesses
    • All Trusted Businesses
    • Dealers – COMING SOON
    • Products – COMING SOON
    • Services – COMING SOON
  • GMA Store (soon)
    • Shop GMA
    • My Account
    • Cart
    • Checkout

Category: Meteorite Primer for Collectors

Hedging the Approval of the CT Group

The search is on, but no need for drones or metal detectors to join this adventure. We’re on the hunt for a handful of already…

Dustin Dickens 16 May 2022

Important Links

  • Protecting Your Privacy
  • Securing Your Information
  • Website Terms of Service
  • Refunds & Returns
  • Shipping
  • Sitemap

Contact & Follow Us

Email us at contact-us@gmeta.org
Follow us on Facebook

Language & Currency

TBD

Recently Active Members

Profile photo of Mikael Vieira
Profile photo of Luca Fenocchio
Profile photo of Scott McGregor
Profile photo of Domjan Svilković
Profile photo of Mendy Ouzillou
See all
AUTHENTICITY, STANDARDS, COMMUNITY,
SERVICE & TRANSPARENCY

© 2023 Global Meteorite Association, Inc. - All rights reserved.

Unless otherwise identified or attributed, all content included in or made available through this website, such as but not limited to text, images, graphics, logos, video clips and audio clips, is the sole property of the Global Meteorite Association and that content's creator, and protected by US copyright & trademark law. No content may be copied, reposted, shared or distributed for any reason without express permission. By engaging with our website, you agree to be bound by our Website Terms of Service, without any limitations.

Forum Description

The search is on, but no need for drones or metal detectors to join this adventure. We’re on the hunt for a handful of already classified carbonaceous chondrites that may soon be part of the new carbonaceous Telakoast (CT) group. So, digital sleuths and number nerds gear-up! We’re searching through collections, eBay listings and bags of stashed stones on this meteorite hunt. Fair warning to our Business members, double check your carbonaceous inventory!

A grouplet of 16 different carbonaceous chondrites which are currently classified as CM2, CM-an, or C-ung, might soon be getting an official group of their own. A stellar team of meteoriticists, including lead author A. Irving, and coauthors J. Gattacceca, K. Ziegler, C. Sonzogni, P. K. Carpenter, and L. A. J. Garvie, have recently proposed this new group in an abstract presented to the 53rd Lunar and Planetary Science Conference titled, CT Chondrites: A Newly Recognized Carbonaceous Chondrite Group with Multiple Members, Including Telakoast 001, Chwichiya 002 and Cimarron. The abstract shows that the stable oxygen isotope ratios of the grouplet plot to roughly the same point against the terrestrial fractionation line, indicating a common parent body. The authors report that all specimens have relatively small chondrules with a mean apparent diameter of 280 μm. They also note that olivine shows Fayalite peaks at Fa3 and Fa40. Perhaps most interestingly, they mention that none of the specimens contain any CAIs. This lack of CAIs is another indicator of a common parent body which was apparently depleted of refractory minerals.

We should keep in mind that this newly proposed group has not been approved by the Nomenclature Committee, and there are no guarantees it will be. Furthermore, oxygen ratios are only one indicator used to determine if meteorites belong to the same group. However, the sheer number and diversity of current classifications that fit into the proposed CT group, all now arguably misclassified, is quite compelling with regards to an expedited approval.

All of this is important because carbonaceous chondrites are uniquely important to planetary science and represent a rich sampling of primitive materials from early in the Solar System’s evolution. They’re rich in water and other volatiles and contain pre-solar grains and refractory minerals (CAIs) that help cosmochemists to determine and further refine the age of our Solar System.

At present the currently recognized taxonomy for carbonaceous chondrites, as reflected in the official Meteoritical Bulletin database, includes: Ivuna-like (CI), Mighei-like (CM), Ornans-like (CO), Vigarano-like (CV), Karoonda-like (CK), Renazzo-like (CR), Bencubbin-like (CB), High-metal (CH), and Loongana-like (CL). The C and C-ung designations without a petrologic type are essentially “old” placeholders for carbonaceous chondrites and should not be considered as distinct parts of the taxonomy as much as holdovers from a less specific time in the evolution of carbonaceous chondrite taxonomy. This point is an important consideration for type collectors. Meteoriticists have increasingly adopted more stringent taxonomy guidelines for ungrouped carbonaceous chondrites, with best practices requiring the -ung designation and an associated petrologic type, e.g., 1,2,3, etc. A great example of this new guideline is the classification of the 25 August 2020 fall in Morocco called Tarda, a C2-ung.

So, what are we looking for in this new CT group? Irving, et al have identified 16 classified meteorites that fall into two petrologic types, CT2 and CT3, including the following meteorites:

  1. CT3: Telakoast 001, Cimarron, Chwichiya 002, NWA 6862, NWA 8781, NWA 12416, NWA 12957, NWA 13671, NWA 13984, NWA 14051, NWA 14139, NWA 14179, NWA 14200.
  2. CT2: NWA 11699, Sarir Tazirbu 001, Qued Mya 002.

While all 16 of the meteorites listed above will be representative in some way of the CT parent body, the crème-de-le-crème is the type specimen, Telakoast 001. Regardless of if you stumble upon a piece of Telakoast 001 or Chwichiya 002, or NWA 11699 they will all be poised to be reclassified as CT. Certain collectors may prefer an aqueously altered CT, in which case one of the CT2 meteorites in the list would be sought out. What’s interesting to note, is that while oxygen plots can reveal parentage and change the primary classification of a chondrite, for example, from CV to CR, it will never affect the petrologic grade. This is because this part of the classification is determined entirely by the geochemical equilibration and aqueous alteration of the meteorite’s primitive minerology. This means the CM2 and C2-ung in the list should map to CT2, and that the C3-ung should map to CT3.

This author’s enthusiasm for the search for these secrets hidden in plain view comes from having already discovered several of the listed meteorites in my own collection. I also enjoy a good scavenger hunt from time to time, and this has a bit of that flavor to it. Though speculation on my part, it seems likely that if the CT group is approved, then the value of these 16 meteorites will increase. There are no guarantees that either the CT group will be approved, or that if it is, it will increase the value of these meteorites, however, seems like a pretty good hedge to me.

Report

There was a problem reporting this post.

Harassment or bullying behavior
Contains mature or sensitive content
Contains misleading or false information
Contains abusive or derogatory content
Contains spam, fake content or potential malware
Activity or speech that violates the GMA Code of Ethics.

Block Member?

Please confirm you want to block this member.

You will no longer be able to:

  • See blocked member's posts
  • Mention this member in posts
  • Invite this member to groups
  • Message this member
  • Add this member as a connection

Please note: This action will also remove this member from your connections and send a report to the site admin. Please allow a few minutes for this process to complete.

Report

You have already reported this .
Clear Clear All