Blog pagination

Hey guys I need help about pagination I m using this code but there is no page numbers on my page.

<?php 

		$lastBlog = new WP_Query('type=post&category_name=blog');

		if( $lastBlog->have_posts() ):

			while( $lastBlog->have_posts() ): $lastBlog->the_post(); ?>

				<?php get_template_part('contentt',get_post_format()); ?>

			<?php endwhile; ?>

<div class="nav-previous alignleft"><?php next_posts_link( 'Older posts' ); ?></div>
<div class="nav-next alignright"><?php previous_posts_link( 'Newer posts' ); ?></div>					

		<?php	endif;

		wp_reset_postdata();

		?>