** Shares in cementmaker GCC up 3% in Mexico City morning trading after the purchase of three aggregates units in Texas

** The $100 million purchase to add more than 4 million metric tons a year of aggregates production capacity to GCC's portfolio

** Shares climb to 184.95 pesos ($9.07) apiece

** "Investing in aggregates makes sense," write Scotiabank analysts in a note to clients

** Scotiabank notes the aggregates market is fragmented and less capital intensive than an integrated cement plant

** The deal should boost GCC's EBITDA some 3%, Scotia notes, and acquisitions in the U.S. should help GCC to reduce exposure to Mexico's heightened country risk

** GCC is also open to listing in the U.S., Scotia says in a separate note

** But the aggregates purchase is more about increasing scale before making a move like a U.S. listing, they add

** Scotia targets GCC at 243 pesos per share, while Banorte targets the stock at 230 pesos

($1 = 20.3873 Mexican pesos)

(Reporting by Kylie Madry and Noe Torres)

((Kylie.Madry@thomsonreuters.com))