Where to buy premium white chalk in the U.S., like they have at RIMS? While not a research-level math question, I'm sure this is a question of interest to many research-level mathematicians, whose expertise I seek.
At RIMS (in Kyoto) in 2005, they had the best white chalk I've seen anywhere. It's slightly larger than standard American chalk, harder, heavier, and most importantly covered with some enamel-like coating that one must rub through (on the end) to be able to write with. One's hands don't rub through the coating, and thus don't get chalky.
Are there any U.S. manufacturers of such?
EDIT: even though someone has given a link whereby to order this stuff from Japan, I would still be delighted to hear about American products that beat Binney & Smith.
 A: If you are looking for something better than Binney and Smith, and don't want to pay shipping from Japan, I really  like Quartet chalk.  They sell it in white:
http://www.amazon.com/Quartet-Alpha-Nontoxic-Chalk-Sticks/dp/B002ZZ9FMC
I have never bought the white, though, so I can't swear by it.  
I do use their triple size ivory chalk.  I like it because it is thicker than regular chalk (so easier on the wrists and arms), and also because it is much denser than Binney and Smith.  You can find it at Office Depot:
http://www.officedepot.com/a/products/342246/Quartet-Alphasite-Triple-Size-Chalk-3/
I also swear by their colored chalk:
http://www.amazon.com/Nontoxic-Colored-Assorted-Colors-QRT305003/dp/B0013CQ38W/ref=sr_1_1?ie=UTF8&s=office-products&qid=1281560371&sr=8-1-catcorr
They do have a stick of white in each packet of colored, and if that is the same as what they sell in what I listed first, then I can vouch for its quality.
One final note: this chalk claims to be low dust.  I disagree.  If you're looking for good dense chalk that shows up really well on the board, this is it.  But if you want to be clean at the end of the lecture, this is not for you.
A: You can buy it online [rakuten link deleted]
Edit (2020-7-10): Hagoromo Bunku company has been shut down in March 2015 (Berkeley Alumni Magazine article).  There were two successors to their product, because the three custom machines they had for making chalk were sold to two parties.

*

*Two machines, together with the rights to the "Hagoromo Fulltouch" name were sold to Sejongmall, a South Korean company.  They have US dollar prices and ship internationally.  Incidentally, the splash screen on their site has pictures of Brian Conrad and Andrei Okounkov pulled from a Japanese TV show about the chalk.


*One machine was sold to Uma-jirushi, a Japanese blackboard maker with plans to expand to chalk. In April 2015 Uma-jirushi announced a new product called DC Chalk Deluxe (DCチョークDX) as "a collaboration with Hagoromo" in its catalog.  However, Uma-jirushi announced on 2020-1-26 that they would discontinue sales of DC chalk on 2020-5-31.
A: My company started selling Hagoromo Fulltouch Chalk through Amazon.
http://www.amazon.com/gp/product/B007R76ND2
If you have any question, please contact me at
kyung@tenbyteninc.com
510-652-1492
Thank you.
Kyung 
Edit: Now you can buy Hagoromo Fulltouch Chalk in color.
http://www.amazon.com/s/ref=bl_sr_office-products/189-2317706-1220456?_encoding=UTF8&field-brandtextbin=Hagoromo%20Bungu&node=1064954
A: Following on S. Okada's post, I recently ordered 12 boxes (864 pieces) for just under $25 per box, or 3 sticks/dollar. Rakuten only ships within Japan, but Tenso
will forward the package abroad for roughly twice the cost of the package itself. However, Tenso is having a promotion till 28 Feb 2012, first 5000 yen discounted to 1000 yen. For a few boxes, jump on this, this is your chance. I went way over so it didn't save me much.
Even though Rakuten won't ship the chalk abroad, their English web form requires a complete US address before a person gets to look at the order. This is easy: Give your US address, but in the comments field, give your Tenso address. This worked just fine for me.
My credit card company put a fraud alert on Rakuten's charge, which canceled the order. Somewhat reasonable if Rakuten doesn't ship to the US, where I am. I had to place the order again, after clearing the fraud alert. Better to warn your credit card company in advance.
My breakdown, 12 boxes was 7092 yen plus 300 yen shipping to Tenso, or 92.62 USD. It arrived within a day. Tenso to NY was 17300 yen shipping plus 2980 yen handling, minus my 4000 yen coupon, or 204.41 USD. If anyone can parse a "slow boat" shipping option that costs less, that would help. Otherwise, I have word of a new importer to the US that should have stock in May, also $25 per box but less adventure to order. I'll post again when that's official.
A: We here in New York have also long sought to secure supplies of this amazingly high quality chalk. It is called Hagoromo "Fulltouch" chalk, and my colleague Jonas Reitz wrote to the company, since the chalk does not seem to be available anywhere in the US, and got a letter in reply directly from the company president (with fairly OK English) concerning prices and rates to the US. It would come to 3 dollars per stick, and we considered that. 
Meanwhile, one of our postdocs with connections to Japan was able to arrange a small supply that way, and this is the message our administrative assistant sent out (provided with permission):


To All GC Math Ph.D. Program Faculty, 
I am happy to report that we have managed (thorough the good graces of our postdoc Yu Yasufuku) to get a limited supply of Hagoromo "Fulltouch" chalk which is made in Japan and is not available for sale in the United States.  We have been trying unsuccessfully to get this “miracle” chalk for years, but finally our prayers have been answered.  Users of this chalk report that it is the “Rolls Royce” of chalk; for you oenophiles, it may be thought of as the “Chateau Lafite Rothschild” of chalk, or, for you baseball fans, the “Babe Ruth” of chalk… well, you get the idea.  
I have heard it said that it is impossible to make a mathematical mistake when writing with this chalk, but I am somewhat dubious of this claim.
The chalk was “smuggled” in stick by stick carried in the beaks of birds (well, practically), so the supply is very limited.  We have, however, worked out a distribution system that seems the fairest and that should allow our stash to last for about 3 semesters. Faculty members teaching at GC will get ten sticks of chalk per semester, and those not teaching but who are coordinating (or co-coordinating) a math seminar at the GC and is a member of the Math Doctoral Faculty will each get 2 sticks per semester.  This will repeat each semester until the chalk is gone.  Faculty should save this chalk for use only during their most important lectures or when working on their most important theorems.  
If you currently fall into one of the two categories listed above, please stop by to see me for your chalk and I will check you off of my list.  Hopefully, after spring 2011, another supply of these magical white sticks can be procured on the black or gray market, or perhaps Hagoromo will begin distribution in the U.S.
At any rate, enjoy your chalk!  Use it wisely.  
Best,
Rob
Robert S. Landsman, Assistant Program Officer, CUNY Ph.D. Program in Mathematics 


A: I was recently pointed to this site for buying Japanese chalk (white and color, Rikagaku brand), as well as other Japanese pens and office supplies. In particular, they sell the Japanese erasers that I believe Dylan referred to in his comment on the original question.
http://www.jetpens.com/
A: Umajirushi DC DX, which is supposed to be based off the Hagoromo formula is available on alibaba. At 24 boxes of 72 each, including shipping, it comes to about 13$ a box of 72. Is anyone interested in sharing an order?
