[docweathers]

How much difference in composition is are likely to be between US suppliers for:

Ferro Frit - 3134
Nickle Oxide, Black
Manganese Dioxide 325 Mesh (Morrocan)
Iron Oxide - Red NR-4284

Thanks Larry

[Mark C.]

docweathers, on 20 January 2013 - 02:50 PM, said:

How much difference in composition is are likely to be between US suppliers for:

Ferro Frit - 3134
Nickle Oxide, Black
Manganese Dioxide 325 Mesh (Morrocan)
Iron Oxide - Red NR-4284

Thanks Larry

Larry
the ferro frit is made under exacting standards by Ferro industries so I'll guess not much.
Not sure about source of nickle ox but I have not noticed much over the years
Managanese-I have a new 50# bag but still have not finished (almost my last 50# bag so I cannot say yet
Red iron you will not notice it at least in most glazes

The thing to keep in mind is these are all mined from the earth and deposits vary so suppliers may have old or new stock with minute differences-most colorants I feel do not change that much. With a few exceptions like rutile
The frits are reground fired glasses so they are controlled to a huge degree.My old frits are very much like the new ones.
If you worry about this just buy lots so you draw for many years from the same bags-also quantity discounts will apply at places like US pigments.com
or Laguna Clay Co (colbalts are always high priced there)-I tend to buy colorants at several supply sources as prices vary- my last buy of colbalt Carbonate I bought 100#s and resold 80% of it to our local supplier-it was chinese and I had a great wholesale connection.
Mark

[docweathers]

Thanks Mark

I will buy in larger quantities as soon as I'm clear on what glazes I'm going to be using most often. At this point I'm such a beginner that I'm just sorting through dozens of cone six glazes on test tiles to see what looks good in my situation and would be worth keeping.

Larry

[Mark C.]

Most likely you will need copper carbonate as well cobalt carb and iron and rutile and managnese
The others less but still a maybe will be copper oxide as well as cobalt ox and black copper ox
This will be a good start.
Mark

[docweathers]

Thanks for the shortlist.

[Marcia Selsor]

recently in Texas there was a shift in talc. Things do change as the mines go through their veins.
Since you are in the NW , you should be able to get Custer feldspar easily. the Bray carries a lot of chemicals that many suppliers don't carry.
molochite for example.
I always check shipping and price per pound. Irons can vary, copper carbonate can vary.Large quantities are a good idea.

Marcia

[Mark C.]

Marcia Selsor, on 20 January 2013 - 10:40 PM, said:

recently in Texas there was a shift in talc. Things do change as the mines go through their veins.
Since you are in the NW , you should be able to get Custer feldspar easily. the Bray carries a lot of chemicals that many suppliers don't carry.
molochite for example.
I always check shipping and price per pound. Irons can vary, copper carbonate can vary.Large quantities are a good idea.

Marcia

Marcia
The shift in talc is/was beyond Texas-its just about everywhere-My matt glaze depends on old school talcs and I have about 5 years supply left. The closest newer talc is serria light from Wyoming and its a little shiny.
I only use pioneer talc in one glaze now-seems talc has gone thru so many changes.
Gone are c-30 talc and desert talc from the old days.If anyone has some of these I'm a buyer,
Mark

[JBaymore]

The reason for the recent talc "shift" was that the older sources were well contaminated with asbestos.

best,

......................john

[Mark C.]

I thought that the asbestos talcs where the ones from New York?
seems odd that many where from all over the country
One would think with the chemical analyses they would catch this on the early side
Mark

[JBaymore]

Chemically asbestos is not different from other alumino-silicate materials.... it is the crystalline sturcture.

Tremoline asbestos and talc tend to run in the same rock strata...... difficult to separate.

http://www.ncbi.nlm....les/PMC1475418/

http://www.ncbi.nlm....les/PMC1475411/


http://www.ceramicar...ploads/2009/02/talc.pdf

http://www.p12.nysed...plan/documents/AsbestosinTalc-101507.doc

http://www.uncashd.o...eases&Itemid=92

best,


..................john

[Mark C.]

Thanks for those John
I read thru them
I could not open this one -you must have a new word version or something else?
http://www.p12.nysed...plan/documents/AsbestosinTalc-101507.doc

But That one on the NYTAL 100 HR is what I recalled all along-old brain memory.
Looks like Texas talc will be the new talc for most.
Mark