Since 2008 researchers at Belle in Japan found hints of a four-quark particle. Those hints were confirmed.

"This reinforces the 5.1σ (4.7σ) rejection of the 2+ (2− ) hypotheses previously reported by the Belle collaboration, and confirms the 3.4σ (3.7σ) indications from Belle that 1+ is favored over 0− (1− )."

Belle collaboration, K. Chilikin et al., Experimental constraints on the spin and parity of the Z(4430)+ , Phys. Rev. D88 (2013) 074026, arXiv:1306.4894.

"The cost [...] has been evaluated, taking into account realistic labor prices in different countries. The total cost is X (with a western equivalent value of Y)" [where Y>X] source: LHCb calorimeters : Technical Design Report ISBN: 9290831693 http://cdsweb.cern.ch/record/494264

or: "1the western equivalent value is 1'390 kCHF. 2the western equivalent value is 5'450 kCHF" http://lhcb.ecm.ub.es/spd/spd/General%20information/spd_cost...

Dead link

New form of matter seems a bit linkbaity... It's a highly unstable particle made of 4 quarks, kind of like a meson (which is a quark/antiquark pair).

> It's a highly unstable particle made of 4 quarks, kind of like a meson (which is a quark/antiquark pair).

I thought the new particles were cool because they don't follow the color charge analogy, whereas mesons do follow the analogy?

The posible colors combinations of the mesons are red+antired, blue+antiblue and green+antigreen. The color+anticolor are not fixed, they “constantly” change. (Actually, any linear combination of the pairs is posible.) http://en.wikipedia.org/wiki/Quark#Strong_interaction_and_co...

There are some abstract algebraic properties of the particles and these properties produce the color rules.

With 4 quarks the only possibility is a mix of 2 quarks (with colors) and 2 antiquarks (with anticolors). For example red+antired+blue+antiblue.