Jump to content

My First Crystalline Attempts

Recommended Posts

Brandon: excellent results for first firing- I know many have not gotten this far in 30 firings. You are to be commended for researching and learning before diving off into the deep end of the glaze pool. I like to use crystalline posts as an educational opportunity for those who are following- there are many. You have the peak temp, growth ramps, and recipe down.  A reactive recipe will grow crystals at the rate of 3/4 to 1" per hour of soak time. 

3 hours ago, Brandon Franks said:

Hey, Guys,


Thanks for all the help you have given me. (Especially, @glazenerd) Here is the first round of my crystalline pieces. The blue on blue and green on green glazes are from a book, and the blue on green is a glaze I created myself!


Enjoy, and thanks again!


Crystal development, growth, field to crystal ratio, and population is spot on. Two items to critique- both relating to titanium. The small secondary crystals are normal- but can be controlled to some degree by lowering titanium additions. The discoloration on the shoulder is also caused by excess titanium  (cloudy). 

55064711-301C-4B8E-B8BB-38F132ABB193 2.jpeg

We talked about copper in PM. When using copper as the primary colorant- cut lithium carb by as much as 1/3 to prevent boiling. That "silver" looking streak on the shoulder is "boiling" from excess flux. Copper also tends to be very reactive to the base recipe and likes to overpopulate. Use the same recipe: cut lithium as noted, and lower zinc by 0.50 to 1.0% Just add whatever deduction you make from the zinc to the silica.


Great crystals on this one- exceptional in fact. Again note the cloudy (milk) on the upper third from excess titanium. I am very impressed with your first firing- very impressed. You can discuss exact recipe in PM if you have more questions.



Link to post
Share on other sites

Lee- I get questions about crystalline on a regular basis in PM and email; and will answer publicly when asked or if from someone I have been working with. I still read what is posted on a regular basis. Been working on a couple of articles for CM about the finer points of firing crystalline glaze: as Brandon just proved in his first firing- not as tough as it looks if you know the "tricks."



Link to post
Share on other sites
  • 2 weeks later...
On 10/11/2019 at 9:56 AM, Cline Campbell Pottery said:

I love those pots.  Could you please tell us what book you used?   I've been making pots for a while but still consider myself a glaze chem beginner, but I'd like to try crystalline.  I'm lucky to have access to both gas reduction and electric ox.



Also in NJ


Sorry for the late reply,


This is the book: https://www.amazon.com/gp/product/0873496035/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1


I have been mixing glazes for quite some time, I would recommend starting on cone 6/10 oxidation glazes, get comfortable with them and then try crystalline!


Link to post
Share on other sites
  • 4 months later...

Crystalline Update:


Achieved round crystals

Ability to control population 

Experimenting with colors

Nearly finalized base recipe

Nearly finalized firing schedule

Improved throwing abilities 



(My attached picture is from my most recent load, I resupplied my zinc and got a very reactive batch, I am adjusting the percentage .75 grams/batch which I have judged appropriate based on the other firing results)



Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...

Important Information

By using this site, you agree to our Terms of Use.