Jewelers of America and the Connecticut Jewelers Association are marshaling their troops to fight a proposal by Gov. Dannel P. Malloy to raise taxes on ­jewelry purchases in his 2012–13 budget.The governor proposed a 3 percent tax on jewelry priced higher than $5,000. Because Connecticut already has a general sales-tax rate of 6 percent (which, under the proposed budget, would rise to 6.35 percent for retailers), this would mean that ­jewelry over $5,000 would be taxed at a rate of more than 9 percent. The luxury tax also applies to automobiles (over $50,000), boats (over $100,000), and cl