Ep. 97 Bill Crowe at The Spellman Museum: Live Expertizing Event Sponsored by NobleSpirit (Part 2)

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  • Опубликовано: 10 янв 2025

Комментарии • 15

  • @chriswhitehouse8982
    @chriswhitehouse8982 11 месяцев назад +3

    Please bring back Conversations with Philatelists, we miss you!

  • @seandail1
    @seandail1 Год назад +1

    This may be the best (2) episodes you have produced. I'd love to see more conversations just like this with expertizers.

  • @godcountrycorps7621
    @godcountrycorps7621 4 месяца назад

    I can't even tell you how much I enjoyed this video. I'd love to see more stuff like this.

    • @NobleSpirit
      @NobleSpirit  4 месяца назад

      We greatly appreciate it! Keep an eye out for more videos just like this being posted soon!

  • @tomsmith822
    @tomsmith822 2 года назад +1

    Most informative and interesting. Thank you for presenting this to us.

  • @vkollekciyu
    @vkollekciyu Год назад

    Спасибо за обзор ! Марки это история ! Это то что должно нас объединять !

  • @rogerturner1881
    @rogerturner1881 Год назад +6

    where are you two

  • @patiencezero-xc9zl
    @patiencezero-xc9zl Год назад +5

    Is this channel still up and running?

  • @2realesazul
    @2realesazul 2 года назад +1

    For the most part philatelists, including this gentleman, have their chemistry completely wrong. We tend to think of aging as an "oxidation" process because if you leave iron out it will rust (oxidize). Poorly kept stamps develop "rust" spots so it must be oxidation, right? Not quite. These are created by microorganisms feeding on the sugars of the gum when the environment conditions (temperature and moisture) are right. So, microbial process, but NOT oxidation.
    Now about inks, which in the XIX century were mostly mineral based. Red pigments may have come from red ochre (a mixture of iron oxides), or vermillion (mercury sulfide) among others. When stored in poorly aerobic, moist conditions, such as inside a box in a basement, these metals will either disproportionate to get to their most stable form or react with its environment, most likely oxidizing the paper they are in contact with. For example, mercury sulfide (HgS) which is red, will go to Hg2S which is black, giving the ink a darker tone. When we think about the metal, this is a REDUCTION process.
    Now the gentleman is correct in saying we restore the original ink colors (the process he calls de-oxidation) with hydrogen peroxide. This chemical is however an oxidant, so his claim to de-oxidize using an oxidant makes no sense. Same for all the stuff about removing sulfur and an extra oxygen radical someplace
    In summary, ink aging is better explained by a REDUCTION process which results in darkening of the color. The process can be reversed by OXIDATION of the inks with chemical oxidants such as hydrogen peroxide.
    Modern inks are a completely different beast as the pigments are made from organic compounds instead of minerals. They tend to deteriorate to lighter shades and their major enemy is sunlight which promotes the generation of radicals. Not the topic of this video so I'll stop here.

  • @allanwestphall8108
    @allanwestphall8108 Год назад +2

    We miss conversations with Philatelists!

  • @SirDeekan
    @SirDeekan 2 года назад +1

    CwP is creeping up on Ep. 100~!~ Would like to be the first to say congratulations! And is there any leaks on if you are planning anything special?

  • @humfelbert2079
    @humfelbert2079 2 года назад

    Very interesting video. Thanks

  • @klocki4699
    @klocki4699 Год назад +3

    What a shame you gave up. Your channel was the best. Sad.

  • @benhancock8143
    @benhancock8143 Год назад +4

    Did you all get lost?

  • @le_med
    @le_med Год назад +4

    Last video was 5 months ago. Are you guys ok what s going on?