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Ask HN: What kind of whiteboard does not use dry erase markers?

32 points dandrew5 | 2 comments | 15 Mar 25 18:46 UTC | HN request time: 0.402s | source

I've been using a dry erase whiteboard for decades and am in the market for something different. Someone mentioned in another thread they were using some kind of magnetic board (maybe it wasn't magnets, I can't remember 100%) but I can't find anything like this online.

Anybody have any recommendations?

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CaffeineLD50 ◴[18 Mar 25 04:24 UTC] No.43395739[source]▶
I recommend chalk. Its a little dusty but works great.

Seems to be nontoxic and low in the chemicals and plastic department.

Chalk. Even comes in colors.

I'm not joking.

replies(2): >>43395799 #>>43424089 #
1. everyone ◴[18 Mar 25 04:36 UTC] No.43395799[source]▶
Also it's actually gypsum. Same material plaster and plasterboard is made from.
replies(1): >>43395844 #
2. cooljoseph ◴[18 Mar 25 04:44 UTC] No.43395844[source]▶
Are you sure about that? According to Wikipedia both gypsum and calcite are used. Apparently, gypsum is used for colored chalk, and calcite is used for white chalk:

> Chalk sticks are produced in white and in various colours, especially for use with blackboards. White chalk sticks are made mainly from calcium carbonate derived from mineral chalk or limestone, while coloured chalk sticks are made from calcium sulphate in its dihydrate form, CaSO4·2H2O, derived from gypsum.[6][7] Chalk sticks containing calcium carbonate typically contain 40–60% of CaCO3 (calcite).

https://en.wikipedia.org/wiki/Blackboard#Chalk_sticks

Wikipedia cites the following articles:

[6] "How chalk is made – material, making, used, processing, procedure, product, industry". madehow.com. Retrieved February 17, 2021.

[7] Corazza, M.; Zauli, S.; Pagnoni, A.; Virgili, A. (2012). "Allergic contact dermatitis caused by metals in blackboard chalk: a case report". Acta Dermato-Venereologica. 92 (4): 436–437. doi:10.2340/00015555-1296. PMID 22367154.

The first of these seems more relevant... I'm not quite sure what the second citation adds.